Copy innerText of a div to an other div

JavaScript
1

Hello! I want to copy the content of one div into another one, however, I got an err saying that the div selected is null. Why is this? How can I solve it?

let foo= document.getElementById("foo").innerText;
let baz= document.getElementById("baz").innerText;
foo= baz;

should I put an event listener with type DOMContentLoaded? I don’t know why the foo and baz are null. They exist in HTML.

	<div id='#foo'>
		foo
	</div>
	<div id='#baz'>
		baz
	</div>
2 
let foo= document.getElementById("foo").innerText;
let baz= document.getElementById("baz").innerText;
foo= baz;

foo and baz variable as you described, simply text not a html element.
Inside html elements foo and baz simply text not a variable, so dom doesn’t know
they are variable. It simply put ‘foo’ and ‘baz’ string.

What you can do as a solution would be, you can store html elements as variables not their innerText, and when the DOMLoaded you can change their innerText by referencing those variables you created.

3 
<body>
<div id=test>I'm Ready</div>
<script>
alert(document.getElementById('test'))
//alerts [object HTMLDivElement]
</script>
4 
<script>
alert(document.getElementById('test'))
//alerts NULL, DOM is not ready
</script>
<body>
<div id=test>I'm Ready</div>
<script>
alert(document.getElementById('test'))
//alerts [object HTMLDivElement]
</script>