If you didn't receive your stimulus checks from 2020 or 2021 then you will have to file a tax return for those years and complete the section relating to the recovery rebate credit. You will see that option after you enter your income and deductions in TurboTax. You will need to download the TurboTax program and prepare the tax return on your computer, it is not available online. You can use this link to download the TurboTax programs from 2020 and 2021: Prior year TurboTax programs
Also, you only have until April 17, 2024 to file the tax return for 2020 to receive a refund, and until April 15, 2025 for the tax return from 2021.