If you have not yet filed your tax return you can go back to the beginning and review your return. To review from the beginning you can Sign back into your Online account, continue past the orange button that says "Take me to my return". Then go to Personal Info at the top of the page and continue through the tax interview to review your entries.
If you are looking to Start Over from the beginning, you can use the Clear & Start Over feature in TurboTax Online as long as you have not yet registered or paid for your return. Please follow the steps below:
https://ttlc.intuit.com/replies/4248526
