ele.addEventListener("click", e=> {
// code to excute
});//HTML
<body>
<h1 id="title">Drum Kit</h1>
<div class="set">
<button class="w drum">w</button>
<button class="a drum">a</button>
<button class="s drum">s</button>
<button class="d drum">d</button>
<button class="j drum">j</button>
<button class="k drum">k</button>
<button class="l drum">l</button>
</div>
<script src="index.js"></script>
</body>
//JavaScript
//number of elements with class of drum
var numOfDrumButtons = document.querySelectorAll('.drum').length;
//assigning the buttons to an array called drums
var drums = document.querySelectorAll('.drum');
//using a for loop to iterate through each arrayed element
for (var i = 0; i < numOfDrumButtons; i++) {
//each array indexed and assigned an anonymous function with alert
drums[i].addEventListener('click', function () {
alert('I got clicked');//for testing
//add actions to occur upon click hear
});
}<element onclick="functionToExecute()">Click</element>