If I don't file federal and state together. If I only file federal thru Turbo Tax. Do I still have to file state separately on my own?
If you do not file both federal and state using TurboTax then, yes, you are on your own to file your state return. You cannot just neglect to file it.
if you don't efile your state thru TT, then your options are
to mail it in or
go to the state website to see if they have a fill in your return and file for free option