I don't have a W-2 to upload because I'm unemployed (student) but I didn't get any 1099-G either.

If you were collecting unemployment in 2021, you may need to check your state's department of labor website for a 1099-G. This is often the same site that you originally signed up for unemployment.

If you were not receiving unemployment, did not have a W-2, or any other source of income, you may not have to file at all. If your parents claim you, they would be eligible for any education credits if you are going to a higher education college or university. 

If your parents do not claim you, even if you have no income, you may still get a refund if you file. If you are within your first four years of school and received a 1098-T from your college, you may be eligible for the American Opportunity Credit. You may also be eligible for the recovery rebate credit if you did not receive the third stimulus payment. It was for $1,400 and most people received it between March and May of 2021.