Can i transfer a 2023 return that was prepared on line to the 2024 return using desktop software?

Unfortunately, you can't import your previous taxes year's data from TurboTax Online to TurboTax Desktop. TurboTax Online can't export anything other than a PDF file, and TurboTax Desktop can't open PDF files. Only .ttxx files 

Thanks for choosing TurboTax

This has been an issue for too long. Intuit should fix it or sell "online" or "desktop only" versions clearly labelled. It's frustrating to say the least especially in this day and age when you have to download the program anyway.. Also who hasn't had to upgrade their hard drive or wipe and reinstall their computer system and was left with nothing. Think it through Intuit!