@Photium First, you parent should have received $2,400 stimulus check in 2020, unless your parents' 2019 AGI exceeded $150,000 when filed as married joint return. You could not qualify for the $500 because you had to be under 17 at the end of the taxable year. If they did not receive the stimulus check for any reason, then they can claim the Recovery Rebate Credit on their 2020 tax return.
Second, your opening bank balance was $3,986.69 plus $1,132.16 from work plus $3.18 from bank interest. Even if you spent your entire bank savings in 2020, then your source of support was only $5,122.03. I presume you did not borrower any money under your own name in 2020, then you did not provide half of your support. In this case, IRS states that your parent can claim you as a dependent, because you are a qualifying child. Remember, if you lived with your parents during the winter break and in the summer, your parents provided support during those periods through shelter and food, and IRS would count monetary value of the shelter and food as parental support.
Third, even if you spent 9 months in an off campus apartment, those 9 months count as time of living with you parents, because those temporary absence from home was for school reason, and your home is still your parents' home for now. After you graduate from college and provide more than half of your own support, then you will have a new home and you are no long a dependent. In the mean time, your parents can claim you as a dependent. Even if your parents refuse to claim you as a dependent, you do not get any tax benefits.
