Help me to make it responsive

Hello! Can someone please help me to make this site responsive, everything is a mess when I try to do something. I thing it has something to do with the background, but I am not sure.

HTML:

<!doctype html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<title>Bergen by bike</title>
<link href="styles.css" rel="stylesheet" type="text/css">
<link href="https://fonts.googleapis.com/css2?family=Courier+Prime&family=Roboto:wght@300&display=swap" rel="stylesheet">
</head>

<body>	
<section class="overlay">
<div class="background">
  
  <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
<div class="topnav">
  <a href="bergenbybike.html" class="active"><img src="../Photos/logo.png" width="102" height="90" alt="logo"/></a>
  <!-- Navigation links (hidden by default) -->
  <div id="myLinks">
    <a href="fana.html">FANA</a>
    <a href="laksevag.html">LAKSEVÅG</a>
    <a href="fyllingsdal.html">FYLLINGSDAL</a>
	<a href="landas.html">LANDÅS</a>
  </div>
  <a href="javascript:void(0);" class="icon" onclick="myFunction()">
    <i class="fa fa-bars"></i>
  </a>
</div>
	
<script>
function myFunction() {
  var x = document.getElementById("myLinks");
  if (x.style.display === "block") {
    x.style.display = "none";
  } else {
    x.style.display = "block";
  }
}
</script>

<hr style="border: 0,5px solid #000000;" />
	
<div class="header">
<p>Welcome to Bergen by Bike!</p>	
</div>
	
<aside class="asideright">	
<img src="../Photos/kartalle.png" alt="map" class="responsiveimage"/>
</aside>
	
<aside class="asideleft">
  <p>
Bergen is a wonderful city, especially if you are interested in the norwegian nature. As a tourist, or even a local, taking your bike on a ride is one of the best ways to experience the beautiful nature. Here you can look at four different routes to take, with different level of difficulties. Remember to bring your helmet, and read our good tips for a perfect ride in Bergen!
</p>
</aside>
	
<div class="rowimage">
<div class="columnimages">
<img src="../Photos/cycling-family-sports-tracker kopi.jpg" alt="family" class="roundimages">
</div>
<div class="columnimages">	 
<img src="../Photos/roundimage3.jpg" alt="family" class="roundimages">
</div>
<div class="columnimages">
<img src="../Photos/roundimage2.jpg" alt="family" class="roundimages">
</div>
<div class="columnimages">
<img src="../Photos/roundimage4.jpg" alt="family" class="roundimages">
</div>
</div>
	
<section class="section1">
  <h1>TIPS FOR YOUR TRIP</h1>
	<hr style="border: 0,5px solid #000000; width:50%" />
	<h2><img src="../Photos/bicycle.png" width="150" height="100" alt="Bicycle"/></h2>
<div class="row">
  <div class="column1">
<p>
<h3>HELMET </h3>
 This is ofcourse the most essential equipment to use. Remember that it’s not always an easy road to ride. Sometimes it can be slippery, or muddy - especially in Bergen where it rains a lot. And also! Wearing a helmet is mandatory.
  <br><br>
 <h3>CHECK YOUR BIKE!</h3>
  Before heading out for a long trip, remember to check that everything on your bike is working. The gear, the breaks, the chains and lights. 
  <br><br>	  
  <h3>WATER AND ENERGY </h3>
  A long trip without any water can become much more challenging than necessary. Remember that either its a workout trip, or a sightseeing tour you need to refill.
  <br><br>
</p>
</div>
<p>
  <div class="column2">
  <h3>MAP </h3>
  If you’re not familiar with the area, make sure you have a GPS or a map to guide you. Remember that the weather in Bergen is unpredictable and it rains alot, so make sure you get home both safely and in time.
	  <br><br>
  <h3>REGULATIONS </h3>
  If you’re not from the area, or the country. Make sure you understand the rules. Both for motorists and pedestrians. 
	  <br><br>
  <h3>FOR THE LONG ROADS</h3>
  If you’re looking to go for the long roads, remember to bring an extra bag with essentials. Extra clothing, food, spare parts and equipment for your bike. 
	 <br><br> 
</div>
</p>
</div>
</section>

	

</div>

	
<footer>Copyright 2020. HIS Design</footer>
</section>
</body>
</html>

CSS:

@charset "UTF-8";
body {
	background: url("../Photos/019solistenbikecitizens7675.jpg");
	background-size: cover;
	background-attachment:scroll;
	font-family: Arial;
	height: 100%;
	color: #232323;
}
.overlay {
	position: absolute;
	top: 0;
	left: 0;
	width: 100%;
	height: auto;
}
h1 {
	text-align: center;
	font-size: xx-large;
	text-decoration: none;
	line-height: 4px;
}
footer {
	font-family: 'Roboto', sans-serif;
	text-align: center;
	padding-top: 20px;
	height: 30px;
	width: 100%;
	background-image: -webkit-linear-gradient(270deg,rgba(255,255,255,0.00) 0%,rgba(255,255,255,0.73) 54.20%,rgba(255,255,255,1.00) 96.27%);
	background-image: -moz-linear-gradient(270deg,rgba(255,255,255,0.00) 0%,rgba(255,255,255,0.73) 54.20%,rgba(255,255,255,1.00) 96.27%);
	background-image: -o-linear-gradient(270deg,rgba(255,255,255,0.00) 0%,rgba(255,255,255,0.73) 54.20%,rgba(255,255,255,1.00) 96.27%);
	background-image: linear-gradient(180deg,rgba(255,255,255,0.00) 0%,rgba(255,255,255,0.73) 54.20%,rgba(255,255,255,1.00) 96.27%);
}
.asideright {
	width: 95%;
	margin-top: 40px;
}
.asideleft {
	width: 35%;
	text-align: center;
	margin-left: 120px;
	font-size: large;
	margin-top: 180px;
	padding-bottom: 50px;
	font-family: 'Roboto', sans-serif;
}
.section1 {
	margin-top: 100px;
	margin-left: 40px;
	margin-right: 40px;
	margin-bottom: 20px;
	font-family: 'Courier Prime', monospace;
}
.column1 {
  float: left;
  width: 40%;
	margin-left: 60px;
	margin-top: 20px;
	text-align: center;
	font-family: 'Roboto', sans-serif;
}
.column2 {
  float:right;
  width: 40%;
	margin-right: 60px;
	margin-top: 20px;
	text-align: center;
	font-family: 'Roboto', sans-serif;
}
/* Clear floats after the columns */
.row:after {
  content: "";
  display: table;
  clear: both;
}
.responsiveimage {
	width: 35%;
	height: auto;
	float: right;
	margin-right: 80px;
	margin-top: 20px;
}
.background {
	background-color: #FFFFFF;
	-webkit-box-shadow: 1px 1px 20px #706F6F;
	box-shadow: 1px 1px 20px #706F6F;
	padding-bottom: 100px;
	margin: 40px auto 0 auto;
    max-width: 980px;
}
.topnav {
  overflow: hidden;
  background-color: none;
  position: relative;
}
.topnav #myLinks {
  display: none;
}
.topnav a {
  color: black;
  padding: 14px 16px;
  text-decoration: none;
  font-family: 'Courier Prime', monospace;
  font-size: 25px;
  display: block;
}
.topnav a.icon {
  background: none;
  display: block;
  position: absolute;
  font-size: 40px;
  right: 50px;
  top: 30px;
}
.topnav a:hover {
  background-color: none;
  color: #97CDAB;
}
.active {
  background-color: none;
  color: white;
	margin-left: 30px;
}
h2 {
	text-align: center;
}
h3 {
	color:#9DE3B7;
}
.header {
	margin-top: 50px;
	text-align: center;
	font-family: 'Courier Prime', monospace;
	font-size: 30px;
}
.roundimages {
	border-radius: 50%;
	width: 150px;
	height: auto;
}
.rowimage {
  margin-top: 100px;
  display: flex;
  text-align: center;
  margin-left: 10%;
  margin-right: 10%;
	
}

.columnimages {
  flex: 25%;
  padding: 1px;
}

/*tablet size*/
@media (min-width: 401px) and (max-width: 768px){

	.background {
	background-color: #FFFFFF;
	-webkit-box-shadow: 1px 1px 20px #706F6F;
	box-shadow: 1px 1px 20px #706F6F;
	padding-bottom: 100px;
    width: 100%;
}
.asideright {
	width: 100%;
	text-align: center;
}
.asideleft {
	text-align: center;
	font-size: large;
	font-family: 'Roboto', sans-serif;
}
.responsiveimage {
	width: 100%;
	height: auto;
	text-align: center;
	}
	.columnimages {
		width: 100%;
	}
	.column1 {
		width: 100%;
	}
}


/*Mobile view*/
@media (max-width: 400px){
}

Hi Heleneis!
Your Html first of all your html is a bit messy:
-keep your inside the tag for better comprehension
-the background tag is referred to all the document without the footer? you meant it to be the overlay section and the background all the body element?

For the Responsive problem, there are some problems, first of all remember that if you set i.e. margin-right:20px; it will use 20px also in the @ media max-width section unless you declare another margin-right property.
So, if you set i.e. the margin-left of your asideleft element at 120px, it will remain at 120px also when you scale your browser window ( that’s not responsive). For modify that you could set as another measure as ( %,em) to be responsive, or you could set a new margin-left property in the @ media max-width property. ( But it 's better to set them with different unity than pixels.)
Also, if you set a width&height of the images in pixels, they will remain fixed.
In example, you setted the margin-left for class column1 as 60pixels, it will remain static, and if you don’t change in the @ media max-width700px the margin will not change.

I hope it was clear. If you have some doubts feel free to reply or write me directly!

The background class is a white layer over the background image. The overlay class is going to be deleted. I just forgot.

I have tried to change my margins etc in the media query, but for some reason the text and images wont center. I think it maybe has to do with the background image, as that is wider than the white layer?? I dont understand, I am pretty new to this. Thank you so much for helping me!

The problem is: your elements are fixed and they will overlap your window size , then your background and overlay are distorted.
If you try to resize your window (until your media query of 700px) you can see that columnimages and responsiveimages are too large for the document.
Try to delete your width size of .roundimages and set it to 20% i.e. and then remove all the width:100% on your images in the media700px. You will see that the window is less messy. But firstly let me know what you are trying to achieve, you want all in a single column when the window is resizing?You want the background be 100% of the width when you resize the image or you want to have some background? The navbar, do you want it always as a button or when you are on larger screen you want the full menu? And the four rounded images ? If you have 4 images with 150px width + padding and margin, when you go under 700px you have to display them in a 2/2 split or all on a column. And let me know what you know ( css grid? css flexbox? bootstrap?) , then i could help you.

Happy to help other people.
Your welcome!