Why do you want to amend your 2019 return? If it is because you think it will result in a stimulus check--it will not. In order to get the stimulus checks you file a 2020 return if you are no one's dependent, and you use the recovery rebate credit on your 2020 return. In order to change your status from dependent to not a dependent for 2019---you AND your parent would both have to amend. And if you were a full-time student until May 2019--it sounds like your parent could claim you for 2019.
If you are trying to get the stimulus checks your 2020 return is the one that controls it now:
The stimulus check is an advance on a credit you can receive on your 2020 tax return. If something went wrong or you did not get the stimulus check in 2020, you can get it when you file your 2020 return in early 2021
The Recovery Rebate Credit will be found in the FEDERAL REVIEW section. ( you should see "Let's make sure you got the right stimulus amount”) If you are eligible it will end up on line 30 of your 2020 Form 1040.
Make sure that you enter ALL of the stimulus money received for the 1st and 2nd stimulus for yourself, your spouse and your children.
Click on Tax Tools on the left side of the screen. Click on Tools. Click on View Tax Summary. Click on Preview my 1040 on the left side of the screen.
Yes, it was to determine if I would receive a stimulus. I did not receive either the 1st or 2nd set of stimulus checks in 2020. After doing so checking, I was not claimed as a dependent nor did I claim myself as someone's dependent in 2019. My income would have put me below the requirement for to receive the 1st & 2nd stimulus check based on my 2019 tax returns. Now, 2020 would be a different. My income increased enough to exceed the income limit for a single filer in 2020 that I would not receive the 3rd stimulus check if I filed my 2020 taxes. I have not filed my 2020 taxes to this point.
I believe I would be eligible for the Recovery Relief Credit, but don't want to miss anything I should be eligible for either.