How do I file if im 17 and got paid cash last year?

You will need to enter you income on Schedule C. You will pay Federal Income Tax if the amount is sufficient and Social Security and Medicare taxes on your profit. 

You are more than likely still a dependent, so you will need to indicate that in the Personal Info section of the return. If you received a Form 1098-T, your parents will claim that credit.

1. Type "Schedule C" in the search field at the top right hand of the screen.
2. Select "Jump To Schedule C" and you will be brought to the section of TurboTax where you can enter or have entered your business income and expense information.