While that doesn’t cover every aspect of emulation, it is most of it. I’m curious what else you would need to know. Everything about emulation is extremely easy to find, nothing about it is hidden away. I’ve been using emulators since the 90’s and it’s not complicated.

I would add to make sure you map your controller buttons in the emulators settings. And if you need a bios/key you can find them by searching for “[game system] bios” and “[game system] keys”.