Arranging elements for mobile

I’m trying to figure out how to make the desktop version of my website work on mobile.

It’s a very “blocky” site and mainly it’s just making the elements in grids, div blocks or cells drop down in the right order instead of being side by side.

Also if you see I’m doing something in a funny way, I’d really appreciate if you can recommend a better way to do things and a bit of “how” as I got a lot to learn with CSS😅

https://formsupreme.webflow.io/
https://preview.webflow.com/preview/formsupreme?utm_source=formsupreme&preview=dc0fec4ce7717ef9ea45be6cea7ebd4e

I really appreciate sharing your valuable time, effort and expertise. Thanks :pray: