Good Games

Good source of games to try: The Video Game Critic. It is possible to order them by rating, like: Colecovision

Most game's manual can be found on archive.org.

SBC Gaming

Odroid GO

SBC - Single Board Computer

Originally it was about building retro game consoles out of cheap SBCs. As it was highly successful, these days there are companies which do release dedicated devices to play retro games (ex: Powkiddy,Anbernic).

If you are interested and want something cheap, but fun, I can recommend getting an R36S device. I bought mine from Aliexpress. Warnings: the included SD card is cheap and can break quickly (get a better one + copy content). The R36S is clone of an another device and interistingly this clone has clones which have some extra issues, the buying guide helps to avoid getting a clone clone.

The SBCGaming Reddit community has a ton more info once you got into the topic.