I'm trying to enter tax paid to one state on another state's return, but turbotax doesn't let me see the amount until everything is done

If you are trying to take a credit for tax paid in another state, you should do that nonresident state first, then the resident state and then the program will transfer all the numbers needed for this credit.  If you have done these states in the wrong order, delete the resident state and do it over.  People get the entries for this credit wrong much of the time.  Go to File in the way upper left hand corner and choose Remove state return..