I wanted to keep my games ideas private for now but the one thing I don't understand how a lotta YouTubers could show their indie game process without it being stolen before release , how? and how does copyright starts in the game industry? 🤔🤔🤔🤔seriously I wasn't taught about it in college

Simple: ideas can't be copyrighted. Also, they're a dime a dozen. Everyone has tons of ideas all the time. Even your average kitten.

Once you release a game, that's another story. I'm not a lawyer, but nowadays copyright is automatic. You publish something, you have rights, period. Protecting your creation is another story. Registration doesn't stop pirates. Ask at your nearest copyright office anyway.