If I file Federal now, can I create and file my CA state return later when all forms are available?

Yes you can.

Yes, the state tax return will not be able to be e-filed until the IRS accepts your federal return.    Once your state forms are finalized and the IRS has accepted your federal e-filed return, your state return will be e-filed.

[Edited 03.18.20 | 2:42 pm]