Is there a way to navigate back to fix the job title? Turbo Tax says my job title has too many characters but I don't know how to go back in and fix it.

"Occupation " is entered in My Info, so you can click edit by your name to get back to those screens.  The IRS only uses occupation for statistical purposes.  It has no effect on your refund or tax due.  So shorten it or change it somehow.

Do you mean your "Occupation?"  

On "Personal Info Summary" page you will see your personal details listed (SSN, Birthdate, Occupation, Resident State):

1. Click on "Edit/Review" button to the right of your personal details. 
2. Find the Occupation box, correct your occupation
3. Click on Continue button.