2021 will not be of any help in doing Turbotax 2025. you'll need to start from scratch. you should get at a transcript (or copy) for the missing years. 2024 may have info that needs to be entered on your 2025 return, the IRS only retains returns for 7 years after that they're permanently deleted. Turbotax only supports the app for 3 years prior to the current year. Currently 2021, with maybe an exception for a few earlier years, is the earliest year that can be opened with the app. after that they cannot be opened even if you have that year's app.
it's advisable to store a pdf copy of each year offline
