The TurboTax Free edition is only available when using the TurboTax online editions. The online editions for tax year 2017 and 2018 are permanently closed.
If you started a 2018 and 2017 tax return using the TurboTax online editions then see this TurboTax support FAQ for completing the 2018 and 2017 tax return - https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-finish-a-prior-year-return-that-i-...
