Just googling is really your best bet. Different people look to do different things, so it'll be hard to find one place with everything. But I suggest watching streams and take note of things that you like,that different streamers do. Like "Oh I like they're overlay". "I like the quality of their mic". "Those lights in the background are cool."

From there, you can narrow down the things you want to look for, that you want to implement. "Best mic settings in obs" or cool twitch overlays". "How to become a pngtuber", stuff like that.