I look at questions like these, and I think that there’s really only one valuable commodity that everyone has—and that is your body. But it’s usually kids who ask these questions, and I’m guessing they have no idea what money is worth, or how to budget, nor many salable skills.
If there were a fourteen year old who was already making a lot of money, say by being an actor, they wouldn’t ask this question. So that generally means little education and skills. And really, the only option for someone with little education and skills is to sell their body.
Again, if someone had whatever it takes to make a lot of money at a young age, they wouldn’t ask this question. Since it is asked, it is reasonable, I think, to assume little education or skill. So if they are serious about making money, they will probably have to do it illegally. Better to revise your goals.