On the off chance this isn't who I think it is, because I know a couple that is exactly in this situation and they also browse 4chan, I'll give you some ideas on how to not screw it up like the girl is, despite her only recently starting.
Don't assume research will give you the key to success. This is not a field where you can apply "logical ideas". You're either gonna gain traction from having a niche or you'll be stuck in obscurity forever. On the chance the latter happens, you CAN come out of it, but you would need to be hard dedicated to it several times a day.
Acknowledge what you're getting yourself into. You're becoming the next stage of an idol. That means you're following the silent rules of an idol. The girl I know wanted to bring in the "4chan crowd" but obviously that'd be a death sentence for a career that appeals to autists and normies. Don't expect to have a chance to be based or redpilled often. Just be yourself but not raw. And as a would be idol, surprise surprise, you're gonna have to put up a facade. That's part of the gig. At least, the facade of always being in character and never letting things get to you. Whatever.
Some others mentioned it before but don't be like a generic zoomer and just shit out buzzword memes. Try to be unique in some way. That's usually the hard part, but don't overthink it.
Also you'd probably wanna start with twitch. From what I've seen, it's extremely hard to be discovered as a streamer on youtube due to it being a "content" platform compared to twitch which is all about streaming. But copyright is usually looser on YT so take that into consideration if you're worried about it.
And lastly, if you're doing this solely for the money, then you better have patience and mental fortitude to deal with weird/hateful comments if you gain traction. If not, then you better back out before the girl ends up mentally breaking down.
Good luck retard.