<!DOCTYPE html>
<html>
<body>
<ul>
<li>Coffee</li>
<li>Tea</li>
</ul>
<p>Click the button to change the text of the first list item (index 0).</p>
<button onclick="myFunction()">Try it</button>
<script>
function myFunction() {
var list = document.getElementsByTagName("UL")[0];
list.getElementsByTagName("LI")[0].innerHTML = "Milk";
}
</script>
</body>
</html>