". . . will the original tax return be restored?"
No. In TurboTax Online all changes are saved immediately and permanently. There is no undo or backout, and no way to exit without saving. It makes no difference whether you file the return or not.
When you start your 2023 tax return it will transfer information from the 2022 tax return. If you have changed the 2022 tax return, the information that is transferred into 2023 will be from the changed 2022 return, not from the return that you actually filed.
Why do you want to make changes to a previous year tax return? Maybe there's another way to accomplish what you are trying to do.
