It would have been nice if there was some list of resources to help people get started with their projects. Something like this: https://gbdev.io/resources.html

Well I know at least one thing: GBDK supports NES. It's not a full game engine, but it can be used when you want to code for the NES in C.

I've added a section to the FAQ: FAQ - NESDev Compo '23 community - itch.io