A way to access onClick or onSubmit on a form

Im wondering what the correct code is for accessing the onclick functionality of a form submit button, so I can edit the error messages.

Ive tried https://www.silvabokis.com/squarespace-tips/dynamic-translation-of-squarespace-form-error-messages

but while the .click works with p tags or img tags it doesn't respond with the submit button using its class or tag.

code Ive tried

  $(document).ready(function(){
    var btn = document.getElementsByClassName([the_actual_button_id]);
    
      $(btn).click(function(){
    alert("The paragraph was clicked.");
  });

 });

site: https://calliope-tarpon-dbkt.squarespace.com

pw frank

Thanks!