It depends. If you file as individual and your income falls under the income requirement threshold, then you may claim the sitmulus as recovery rebate credit on your 2020 tax return. Most taxpayers who are eligible for the Recovery Rebate Credit already received the first and second stimulus payments. You need to fill up the Recovery Credit form on the return and enter zero on both 1st and second stimulus payments line to claim the credit.
See, pub 5848, recovery rebate credit, link
