I’ve never filed taxes before, before i turned 18 my dad got my stimulus checks and ssi bc he is retired so do i have to add that when i file taxes as my income,

Correct- even though your father got the stimulus FOR you on his tax filing, you did not receive it so since you are 18 you can file this year.

You always file your own tax return for income that you earned in your own name from working. The only time your income might be included on a parent‘a tax return is if it is only from investments.

when you file your tax return, you are you. You report your income and your deductions and you pay whatever tax you owe. The stimulus payments are never taxable income to begin with, and any stimulus payments that someone else might have received because they claimed you as a dependent have nothing to do with your income tax for the income that you have earned.

However, if you qualify to be claimed as a dependent by someone else, you must check the box that says “yes, I can be claimed as a dependent“. And this will disqualify you from receiving any stimulus payments in your own name. Even though your father is retired, he likely qualifies to claim you as a dependent; if you are under age 19, and if you lived in in his home more than half the year, and if you did not pay more than half your own financial support.

If you were a minor your parent received your SSI as guardian.

The tax document for that amount will show your name and SSN and you report that on your own tax return.