I would rather e-file my taxes. I don't have a printer.
You select how to file the tax return in the File section of the program on Step 3. Indicate that you want to e-file.
Or see this TurboTax support FAQ for changing from mail to e-file - https://ttlc.intuit.com/community/e-file/help/how-do-i-change-from-mail-to-e-file-in-turbotax-online/01/26985