Inputing HTML for Multistage form

I am trying to input the HTML from this WIX help form ( https://www.wix.com/code/home/example/Multistage-Form) but when I paste it in, the coding doesnt work. Is there a more simple way to make a multistage form so a user can click through questions rather than filling out a single form with multiple questions?

(While also collecting their responses)

Hi,
You should click on the " Open In Editor " button to get the form on your editor.
Note that the $w code, should be added to the code editor. In order to view the code, you should enable the Developer Tools . Click here to learn more about the Code Panel. Make sure that the elements that you add have the same IDs as written in the code.

I hope it’s clear.

Good luck!
Tal.