How do you clear the information on a previous tax year that was never filed?

[Sharmaine]

The online version is for the current year only. If you did not file 2017, that information will not be on the online version for 2018. However, if you need to clear your return and start over, click on Tax Tools from the Menu. On the Menu you will see Clear & Start Over. 

This FAQ will guide you.
How do I clear and start over in TurboTax Online?
https://ttlc.intuit.com/replies/4248526

This Turbo Tax FAQ will show you how to complete your 2017 if you need to complete it.
How to complete a prior year.
https://ttlc.intuit.com/replies/4186197