How to do a "family home computer" these days?

This may be off the mark, but the college I worked at would sell their obsolete computers. They may be 4 or 5 years old, but I think it would do what you want it to do.
Heck you can get super tiny Windows computers for under $150. All peripherals separate, of course.

Example (and not an endorsement):
https://www.amazon.com/GMKtec-Mini-PC-Computer-N100/dp/B0CH81C4K3/?tag=associatessrp-20