child actor?

Anyone know how to become a child actor? i am constantly applying for anything that I can but I never really hear back. I have heard back from stuff a few times but due to my reasons I have had to turn them down. Like how do I find a good agent? Like I know becoming an actor takes time But I wanna be famous. Like Milly Bobby Brown or Noah Schnapp. They became famous young. I know people say not to go into the acting world so young but this is what I want. acting makes me happy. It's what I am good at. It keeps me sane. I am willing to slowly work my way up, no matter how long it takes. I am ready to be on TV!