How to distribute the Internet on 2 subnets?

Question

Computer networks

People tell me how to set it up.
so that the Internet is distributed on 3 subnets

Answer 1

Buy separate cheap routers for two additional subnets.

Answer 2

with a dumb router in any way =)

Answer 3

A smart router can be easily made from an old computer + freebsd. The internet is full of instructions.

Answer 4

And what kind of router?