You can no longer file a 2018 tax return for free using TurboTax. The TurboTax online editions for 2018 which have the Free edition has shut down to make way for the 2019 online editions.
To complete and file a 2018 tax return with TurboTax you would need to purchase, download and install on a personal computer one of the 2018 desktop editions from this website - https://turbotax.intuit.com/personal-taxes/past-years-products/
A 2018 tax return can only be printed and mailed, it cannot be e-filed.
