JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>
<script src="https://code.jquery.com/ui/1.12.1/jquery-ui.min.js"></script>
 <div id="dialog-confirm" title="Ready?">
         <p>Are you sure?</p>
     </div>

    <form action"" id="myform" name="myform2" type="post">
        <input type="submit" value="Yes" name="moveOn" />
    </form>

JavaScript

$(function() {
  var postForm = false;
  $("#dialog-confirm").dialog({
    resizable: false,
    height:190,
    autoOpen: false,
    width: 330,
    modal: true,
    buttons: {
      "Yes": function() {
        postForm = true;
        $('#myform').submit();
      },
      "No": function() {
        $("#dialog-confirm").dialog("close");
      }
    }

  });
    
  $('#myform').on('submit', function(e) {
    if(!postForm) {
      e.preventDefault();
  	  $("#dialog-confirm").dialog('open');
    } else {
      console.log('form submitted.')
    }
  });
});