Does anyone know how creating a 3d cube with rotation would work?

Hey ThatMoobloom here,

There are many ways to create 3d objects in scratch and most of them are using the pen block.
You can acces this by creating a new project in scratch and going to the code section. Al the way at the button there should be a button with a plus sign. here you can add extensions. Select pen and enjoy your new pen blocks.

I'd recommend these projects to understand how creating 3d projects in scratch is possible :

https://scratch.mit.edu/projects/2855520/ This one is to make an rotating cube using wire frames.
https://scratch.mit.edu/projects/396207097/ This one is an tutorial on how to create an 3d maze using raycasting techniques.

If you read all of it including the instructions and notes in the script itself you should get a good idea on how it works.

These ones are to show you what can be done using various 3d techniques:

https://scratch.mit.edu/projects/710170957/
https://scratch.mit.edu/projects/103105245/
https://scratch.mit.edu/projects/681136341/

I'd recommend using turbowarp on the last one. Turbowarp is a site that lets you run scratch projects smoother. Instructions on how to use this are in the games instructions

Of course you can do your won research by typing 3d or pen as a keyword in the scratch search bar.
I hope this was helpfull in any way.

Ok thanks!

uwu