Out of curiosity I wanted to deep dive into emulation, I’m not disappointed :)
I started to work an a CHIP8 emulator which is the easiest emulator one could write. This was quite easy and I wanted to learn more, this is why I started to work on a Game Boy emulator.
The challenge is a way harder. As an example, the CHIP8 has 35 different instructions while the Game Boy has about 500.
They are a lot of information and tutorial about emulation but some are wrong and others are outdated. The hardest part is to dig into all information to cross check everything you find.
The good point is that there is an awesome active community around emulation.
If you want to feel a bit nostalgic, here are "Pokemon Red" and "The Legend of Zelda: Link's Awakening" intros.