how to delete transferred tax data in 2025 return and enter manually?

You should be able to clear and start over, then say no to transferring your data. 

As long as you haven't submitted payment, deducted the TurboTax fee from your refund, or registered, you can erase your return and start from scratch in TurboTax Online.

1. Sign in and select a topic to continue your return.
2. On the next screen, from the left-side menu, select Tax Tools, and then Clear & Start Over (select the menu icon in the upper-left corner if you don't see this menu).
3. Answer Yes in the pop-up to confirm.

If i t doesn't let you say no to transferring, there is a tricky way to clear out transferred info in the Online version. But doing this will also clear out all your current entries. Go to Tax Tools -> Tools -> Transfer from your computer -> Continue -> then Continue without transferring.