document.getElementById in JS+w3schools code example

Example 1: document.getelementbyid() javascript

var x = document.getElementById("demo");   // Get the element with id="demo"
x.style.color = "red";                     // Change the color of the element

Example 2: how to use document.getelementbyid

<p id="YourId">How to use document.GetElementById in HTML</p>
<script>
  function demo(){
document.GetElementById('YourId')./* The thing you need to do to your code... Here I want .innerHTML you can take any...  */.innerHTML('/* what will it change... */')
  }
</script>
<!-- Now execute it by writing the button tag!--><button onclick="demo()">Click Me!!!</button>