You can efile now and print the return later. Save the PDF to your computer for future use.
If you efile you don't mail anything in. Just keep a copy for yourself. Either a printout or the pdf.
If you used the Online version you should always save both the PDF file and the tax data file each year (before online closes Oct. 15) so you have a copy when you need it or if you ever need to amend it in the future. You shouldn't rely on getting a copy from Turbo Tax. Or if you want to use the Desktop program next year so you can transfer from this year.
Turbo Tax Online automatically saves
https://ttlc.intuit.com/community/saving/help/how-do-i-save-my-work-in-turbotax-online/00/26235
Save the PDF
Save the tax file
Always print a copy of your completed tax return for your records, and review it carefully before e-Filing.
You will need it if you are audited by the IRS, or to amend if a TurboTax update changes your return or for any other reason,
AND, to find your AGI next year.
Put it in the drawer and come back in three days.
You will inevitably find something wrong.
I guarantee it.