Like if you choose option A in #dropdown1 you can see and answer #dropdown2, if you choose B than you have to answer #dropdown3
I've tried this :
$w("#dropdown2").hide();
$w("#dropdown3").hide();
let x = $w("#dropdown1").value;
let y = $w("#dropdown2").value; let t = $w("#dropdown3").value;
if (x===A){
$w("#dropdown2").show()};
if (x===B){
$w("#dropdown3").show()};
Hello.
You can follow the cascading form and Hide & Show Elements examples.
Good luck!