How do you create a 3D rectangle?

Answer 1

rectangle is 2D shape

Answer 2

This is a good tutorial for it.
https://www.khanacademy.org/computing/computer-programming/programming-games-visualizations/programming-3d-shapes/a/what-are-3d-shapes

Answer 3

Rectangle is a 2D shape itself, but a 3D rectangle could mean a rectangle inside a 3D space ^^
In Html, you could easily produce 3D rectangles by using the 'perspective' css feature on an element container and then use 'transform' on 3D space rather than 2D...

https://css-tricks.com/almanac/properties/p/perspective/