How to print and mail your return,
https://ttlc.intuit.com/community/printing/help/how-do-i-print-and-mail-my-return-in-turbotax-online/00/26258
When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s. Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS received the return. Don’t forget state.
Important! Mail Federal and State in separate envelopes and mail each year in separate envelopes.
By the way, They are not processing mailed returns right now.
See this IRS page for the latest information
https://www.irs.gov/newsroom/irs-operations-during-covid-19-mission-critical-functions-continue