You will have to ask them for a copy. If they used Turbo Tax online you need the log in info and password. If they used a desktop program they will have to give you a copy. They should have given you a copy when you filed.
If you can't get a copy of your prior year return that was not prepared in TurboTax, but you saved a PDF file of your 2023 return on your computer, you may be able to transfer it into TurboTax Desktop for 2024.