You should be able to choose that option fo pay the TurboTax fees out of your Federal refund once all your forms are finalized and available for efiling, since that option requires efiling. It also requires direct deposit (to a bank account or prepaid card) to receive the refund, and a US address.
For instance, if you have a Form 1040 or 1040A, those won't be ready for efiling until January 18 (projected.)
Federal forms availability dates:
https://ttlc.intuit.com/questions/1908854-forms-availability-table-for-turbotax-federal-products-exc...
Also be aware that the option to pay out of the Federal refund (aka "refund processing service" or in California "Premier Services") has a 39.99 service fee. You can avoid that fee by paying upfront with a credit/debit card or a prepaid debit card you buy in many stores.
