okay so can someone explain how Uta became a part of the clowns? When did he become a bad ...

Go back and read Tokyo Ghoul. Uta isn't necessarily bad nor good. He's always been wanting to destory stuff and ruin people--even other ghouls. Kaneki's in this mess because of the clowns (and others). They have fun doing this. We don't know how he became part of the clowns, he barely has a backstory (yet).

I think he was basically always a part of the clowns (though we were never told when) he was part of the clowns in Tokyo Ghoul