ARTIX LED Backlit Keyboard, Mechanical Retro Typewriter Style with Blue Lights, Metal Base, Round Keycaps (Small)

This has small, medium, and large variants, but no difference in images between them. Whats the difference between the size variants of this keyboard?

How do you change the backlit color?

which switches are used in this keyboard? what is the actuation rating for the switches? are the keys metal? is the bottom metal?

Can this be used with a chromebook?