A script or code can detect whether the client uses or enable the ad blocker.

detect-ad-blocker.html

<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
<script>
  $.ajax({
    url: 'https://static.doubleclick.net/instream/ad_status.js',
    success: function( data ) {
      console.log("Ads loaded");
    },
    error: function( data ) {
      console.log("You're using an ad blocker.");
      document.body.innerHTML = '<center><br><h1>Turn off your Ads Blocker and refresh the page!</h1></center>';
    }
  });
</script>

don't use jQuery for every small things 🥺😐

// create a XHR object
  var xhr = new XMLHttpRequest();
  // open the XHR object in asynchronous mode
  xhr.open("GET", "https://static.doubleclick.net/instream/ad_status.js", true);
  xhr.onreadystatechange = function() {
    if (xhr.readyState == 4 && xhr.status == 200) {
      // OK! we have a successful response.
     console.log("Ads loaded");
      // do something else with the response
    }
    else {
       console.log("You're using an ad blocker.");
    }
  };
  // make the request
  xhr.send();

Did you tested this? 🤔