Can someone explain it better?

Tell us what’s happening:

Your code so far


<style>
  .item1{background:LightSkyBlue;}
  .item2{background:LightSalmon;}
  .item3{background:PaleTurquoise;}
  .item4{background:LightPink;}
  .item5{background:PaleGreen;}
  
  .container {
    font-size: 40px;
    min-height: 300px;
    width: 100%;
    background: LightGray;
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    grid-template-rows: 1fr 1fr 1fr;
    grid-gap: 10px;
    /* change code below this line */
    
    grid-template-areas:
      "header header header"
      "advert content content"
      "footer footer footer";
    /* change code above this line */
  }
</style>
  
<div class="container">
  <div class="item1">1</div>
  <div class="item2">2</div>
  <div class="item3">3</div>
  <div class="item4">4</div>
  <div class="item5">5</div>
</div>

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36.

Link to the challenge:
https://learn.freecodecamp.org/responsive-web-design/css-grid/divide-the-grid-into-an-area-template

Just go to challenges i don’t understand it.

Yes, zero, the more specific your question, the easier it is to help you. There are no dumb questions, but we still need a question. We can’t start at the beginning of web development and work our way up until we find the problem.