If there is no income entered on the tax return, then it cannot be e-filed but will have to be printed and mailed.
See this TurboTax support FAQ for printing a tax return for mailing - https://ttlc.intuit.com/community/printing/help/how-do-i-print-and-mail-my-return-in-turbotax-online...
Note - If you had no income of any kind there is no reason or need to file a tax return. The IRS will not process a tax return with no income entered.
