It won't let me go to next step after asking me how I'd like to receive my tax return. The next step is to sign an file. Can you please help me?

Please run the review section again to catch any errors before visiting the file section again. 

Also, if there are forms in your return that have not yet been finalized, you won't be able to file.  Please check the link below for estimated finalized IRS form dates.

https://ttlc.intuit.com/questions/1908854-forms-availability-table-for-turbotax-federal-products-except-business