Since your federal return isn't ready, it is probably better to file an extension for your state, too, as items missing from your federal return may impact your state return. If you still wish to file your state return now, you'll have to file a paper return since you can't e-file a state return before your federal return is e-filed.
Please see the FAQ below for more information.
Can I e-file my state return before my federal? https://ttlc.intuit.com/replies/3301358