Yes, Lemmy has interest groups known as “communities”. This one is named “Nintendo”, for posts relating to Nintendo games and consoles. Your Lemmy client should display that information on the post list, and in the post itself.
Most people are familiar with reddit, and Lemmy is organized in a similar manner. If you’re new to Lemmy and not familiar with reddit, you can get up to speed by reading the introduction: https://join-lemmy.org/docs/index.html
If you have a PC, they run very well in an emulator. Dolphin even runs on Android, though I’ve never tried it so I can’t judge its performance.