What you're looking for is a single summary page, the "Electronic Filing Instructions" for your state tax return. That page will contain what options you selected to pay your state taxes. This page is likely the first page of the PDF of your state tax return.
It seems a little strange, but you'll re-open your tax return using the instructions I'm linking below. You'll tell the program you're adding a state (and you don't), but that will re-open your returns. DO NOT make any changes to your tax return. You can view how you elected to pay your OK state taxes.
How do I review the method I chose to pay my taxes?
Check the printout or PDF of your return; look for the state cover sheet with the Turbotax logo. If you owed tax, it will show the payment information and how/when you decided to pay. Read the state payment instructions carefully since most states cannot be paid from within the TT system and requires additional steps.