Hide form content until button is clicked

I would like to hide the content of my form until the button is clicked, the code I am using shows content until clicked, I am starting out so probably missing something simple, any help appreciated, the code I am using is:

<script>
function myFunction() {
  var x = document.getElementById("myDIV");
  if (x.style.display === "block") {
    x.style.display = "none";
  } else {
    x.style.display = "block";
  }
}
</script>

>Solution :

you must add "display: none;" to "myDiv" property in css file then you can use your func