here is the basic rundown, dont quote me on the numbers im just going off what i know..
if you make more than 600 year, its taxable, but regardless of what amount you make, you should still make it a habit of filing your taxes every year ( while filing, even if you dont owe anything, its good just to practice, etc)
any type of income you receive, regardless if its in paypal or in person, is usually taxable. In general, if you are a freelancer, you should be expecting to set aside 30% of all your earnings to taxes. Usually, when you work for someone, 15% is used to go towards ss, and medicare, etc, while the other 15% is covered by your employer, however since you are self-employed, its up to u to cover that extra 15%.
Since before I was 18, i've been freelancing so my paypal is legally in my parents name, so they file it under their taxes. Just be sure that if its in your parents name that you are telling your parents what u make because paypal DOES send all financial information to the IRS.
Now if you want to be a bit daring, and do your own thing, you will want to read up on filing Schedule C, which is for people who self-employed/freelance. If you work a normal job and freelance, you still want to do the Schedule C. In some situations you can find yourself paying little to no taxes ( in my case, wont explain how tho
), but just make sure to dont skip it, cuz thats a no no.