Javascript disable function after 1 click

just do re-assignment.

window.onclick = function() {
 document.getElementsByTagName("body")[0] = window.open("https://google.com");
 window.onclick = ""
};

You can achieve this by defining a function that handles the open window behaviour, and then binding that function to the click event for the document's body element.

To prevent the event from firing a second time, call:

document.body.removeEventListener('click', onClickBody);

from within the handler to "deregister" that click event which prevents the popup behaviour from being executed on subsequent clicks:

function onClickBody() {
  
  // Cannot call this in snippet
  // window.open("https://google.com");
  alert('window.open("https://google.com");')
  
  // Remove this event handler to prevent the event handler from being
  // fired again on subsequent body clicks
  document.body.removeEventListener('click', onClickBody);
}

document.body.addEventListener('click', onClickBody);

Body fires click once

You can add an event listener that fires once with the native "addEventListener" like this:

document.body.addEventListener('click', function(){
    // your code here
}, { once:true })

You can read more about addEventListener and its options here: https://developer.mozilla.org/de/docs/Web/API/EventTarget/addEventListener#Syntax

If you wan't to achieve the same behaviour with jquery (you tagged your post so), there is the "one" function: http://api.jquery.com/one/

You use it like this

$(document.body).one('click', function(){
    // your code here
})

One option is to create a variable that updates after the function is runned for the first time.(this works for any function)

<script type="text/javascript">
   var enabled = true;
   window.onclick = MyPopUpLink;
   function MyPopUpLink() {
        if(enabled == true){
          document.getElementsByTagName("body")[0] = window.open("https://google.com");
          enabled = false;
        }
   };
</script> 

The other option is to use addEventListener event without any function.
But this works for events only.

document.addEventListener('click', () => {
    window.open("https://google.com");
}, {once: true});

You could also use the inline event onclick="MyPopUpLink()"

Try this snippet.

let counter1=0;
window.onclick = MyPopUpLink;
function MyPopUpLink() {
if(counter1===0){
  document.getElementsByTagName("body")[0] = window.open("https://google.com");
  counter1++
}
}