If you have income in more than one state or you moved to a different state during 2018, TurboTax will prompt you to file the returns in those states based upon how you completed the personal information as to whether you moved or if you made money in more than one state.
Here is more information about filing returns in more than one state, plus note the links at the bottom related to how to file a non-resident state return or a part-year resident state return, depending upon your situation.
https://ttlc.intuit.com/replies/3300797
