Am I being scammed for a collab on TikTok? (Pictures added)

I have a small following on TikTok and was offered to endorse a small brand for 300 bucks. I said yes ofc because I’m a broke highschool student but now I’m getting a bit skeptical. They sent me a form that asked for my address, name etc (I linked photos) and I asked the person who contacted me if I could use a P.O Box instead of my address and I didn’t put down any bank info. They said that that was ok. But they ended up asking what bank I use to endorse the check which makes sense to me but idk if that’s bs or not. They also said the check would be emailed to me but idk if that’s a real thing. I know I sound stupid but I’d rather be safe than sorry.