when you e-file no physical signature is required only your prior year AGI. as you go through the process of preparing and then filing your return you get to a point where you select to e-file (or mail) if e-file is selected further on there's a page with an icon that says submit which you click on to e-file.
if you are going to mail in your return then you need to print out a copy of your return (just the pages to be filed) actually sign and date the return and mail it according to Turbotax filing instructions. DO NOT MAIL IT TO TURBOTAX. use a method where you can either track it or get proof of delivery.
you can not print out a .tax2020 file.
see this link for printing out your online return.
https://ttlc.intuit.com/community/printing/help/how-do-i-print-and-mail-my-return-in-turbotax-online...
