Sports betting tax question

Hello,

This is kind of a weird question and idk if I’m gonna get hate for it but here we go anyways. I am 18, and live in IL, but have been using my brothers (22) social security number to gamble on sports with my money. I’ve cashed out about $500 profit, with another 300-400 in my account. I know this isn’t much at all, but idk if this will become a problem if I keep making profit. Do I need to pay taxes on this money, or is he gonna get screwed for having unpaid taxes under his social? I just want to know what I have to do so I can talk to him about it and figure out what to do.