Hello, I was always claimed dependent but this year I am filing single. In the year 2020 I was a grad student paying for my tuition. I made no income

Yes, but you may have to mail in a paper return.  TurboTax is working on making it possible to e-file, but haven't heard if that is yet available. 

But first you need to re-examine your premise that you are not a dependent.  I assume you want to claim the stimulus money.  Under the CARES Act, if you are claimed, or qualify to be claimed, as a dependent on someone else’s return you cannot receive a stimulus check, in 2020*.   

There are two types of dependents, "Qualifying Children"(QC) and standard ("Qualifying Relative" in IRS parlance even though they don't have to actually be related). There is no income limit for a QC but there is an age limit, student status, a relationship test and residence test. 

The support test is different for each type. The support test, for a QC, is only that the child didn't provide more than half his own support. A person supporting himself on  scholarships is not considered self supporting. The support test for a Qualifying Relative is only that the taxpayer provided more than half the student's support.

A child of a taxpayer can still be a “Qualifying Child” (QC) dependent, regardless of his/her income, if:

1. He is under age 19, or under 24 if a full time student for at least 5 months of the year, or is totally & permanently disabled
2. He did not provide more than 1/2 his own support**. Scholarships are considered third party support and not as support provided by the student.
3. He lived with the parent (including temporary absences such as away at school) for more than half the year

A person can still be a Qualifying relative dependent, if not a Qualifying Child, if he meets the 6 tests for claiming a dependent:

1. Closely Related OR live with the taxpayer ALL year
2. His/her gross taxable income for the year must be less than $4300 (2020).
3. The taxpayer must have provided more than 1/2 his support

In either case:

4. He must be a US citizen or resident of the US, Canada or Mexico
5. He must not file a joint return with his spouse or be claiming a dependent of his own
6. He must not be the qualifying child of another taxpayer

*If you qualified as a dependent for 2019, but will not be for 2020, you will most likely get the stimulus in 2021, when you file a 2020 tax return.

**The support value of the home, provided by the parent, is the fair market rental value of the home plus utilities & other expenses divided by the number of occupants.

The IRS has a worksheet that can be used to help with the support calculation. See: http://apps.irs.gov/app/vita/content/globalmedia/teacher/worksheet_for_determining_support_4012.pdf