JAVASCRIPT CONFIRM BOX EXAMPLE
Run 
<html>
  <head>
        <script type="text/javascript">
            function isConfirmed() {
                let conVal = confirm("Are you ready to confirm?");
                if (conVal == true) {
                    document.getElementById("result").innerHTML = "Confirmed !";
                } else {
                    document.getElementById("result").innerHTML = "Cancelled !";
                }
            }
        </script>
    </head>
    <body>
    <form>
        <input type="button" onclick="isConfirmed()" value="Want to confirm ?" />
    </form>
    <p id="result"></p>
  </body>
</html>