По кликата на html, js

javascript onclick

document.getElementById("myBtn").addEventListener("click", function() {
  alert("Hello World!");
});

събитието натискане javascript

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

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

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

 document.getElementById("Save").onclick = function ()
    {
     alert("hello");
     //validation code to see State field is mandatory.  
    }

натиснете бутона javascript

// Create variable for what you are trying to click
let button = document.querySelector("#IDofItem");

// Click the button

if (button) {
  button.click();
}
else {
  console.log("Error");
}