I'm new to programming. I've learned a little bit of JavaScript and I made a code. It was all fine when everything was true, but I needed to add something to happen when it is false. So I added a `while` and it didn't work out for me. Someone can help me please? Thank you for the answers!

```html
<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8"/>
    <link rel="stylesheet" href="styles.css"/>
    <script src="JavaScript.js"></script>
    <title>
      Hello
    </title>
  </head>
  <body>
    <p id="Hello"></p>
    <script>
      function onload() {
      alert("choose a number between 1 and 9");
      var Multiply1 = prompt("Multiply this number by 9");

      while (Multiply1 % 9 != 0) {
      alert("This can't be true");
      var Multiply = prompt("Multiply this number by 9");
      }

      while (multiply1 % 9 = 0) {
      var add = prompt("Add the 2 digits you have");
      }

      while (add != 9) {
      alert("This can't be true");
      var add1 = prompt("Add the 2 digits you have");
      }

      while (add = 9) {
      var decrease = prompt("deacrease the number you have chosen from the number you got:");
      alert("the number you have chosen is " + (9-decrease));

      }
      }

    </script>
    <noscript>Please enable JS</noscript>
    <button onclick="onload()">Cilck on me to start"</button>
  </body>
</html>
```