Can you create 3D games and programs in Petit Computer?

Can Petit Computer BASIC for the Nintendo DSi/3DS create 3D games?

Yes. Be aware that Petit Computer BASIC doesn't have any access to the software acceleration and the ability to load in 3D assets of other programming languages. It also doesn't have built in 3D capabilities. (such as a DRAW3D command)

You'll need to create your own 3D code by hand.

Do you remember the Japan exclusive game X, produced by Argonaut Software? That was a 3D flying game that was created on the Nintendo Game Boy in 1992. The code had to be created by hand for rendering the 3D effects since the Nintendo Game Boy had no bulit in 3D capabilities.

Also, retro arcade games like Pole Position and retro console racing games like Super Mario Kart and Top Gear used 2D graphics with 3D programming effects to create a 3D environment.

You will have to program a 3D game in the "old school sense" in Petit Computer for the Nintendo DSi / 3DS.