Check out example codes for "calling function on click html". It will help you in understanding the concepts better.

Code Example 1

<button onClick="script">

Code Example 2

<img src="hospital.png" id="hospitals" onclick="damarkers();">

Code Example 3

var myElem = document.getElementByID('ElemID');
myElem.onclick = function() {
	//do stuff
}

Code Example 4

<button onclick="myFunction()">Click me</button>

<p id="demo"></p>

<script>
function myFunction() {
  document.getElementById("demo").innerHTML = "Hello World";
}
</script>

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