See the instructions in the TurboTax FAQ below to remove the LIVE option for your 2018 return.
https://ttlc.intuit.com/replies/6420172
Now, if you need to prepare a 2017 return, you'll need to purchase the 2017 TurboTax Desktop (CD/Download) edition, prepare and sign your return, and mail it in. Prior-year returns cannot be e-filed. See the instructions to file your 2017 return below.
https://ttlc.intuit.com/replies/3301770
*** I am NOT a tax expert. I am a seasoned TurboTax user, and volunteer to provide assistance to TT users. Nothing I post is to be considered TAX ADVICE; I bear no legal liability for responses.***