how to call button click event using web component in javascript code example

Example 1: how to call a function with a button in javascript

<script>
		function myFunction()
		{
			document.write("<h1>HELLO</h1>")
		}
	</script>
<button onclick="myFunction()">Click</button>

Example 2: javascript click event

// EXAMPLE: 
document.querySelector(`.check`).addEventListener(`click`, 
   function () {
      console.log(document.querySelector(`.guess`).value;
   }
);

// SYNTAX:
//  <element-select>.addEventListener(`click`, 
//     function () {
//       <what-you-want-to-execute-when-clicking-on-element>
//     }
//  );