Can I correct an error on a return that I just completed and printed (2017) Already paid for

[xmasbaby0]

If you were working on a 2017 return you had to be using 2017 desktop software--you were not using the online program, were you?---so of course you can make changes and then print it out again with the corrections.  The return cannot be e-filed.  It has to be signed and mailed.

You are posting from TurboTax Live Self-Employed--which is ONLY for a 2018 return--you did not use it for a 2017 return, we hope.