If you mean paying for the TurboTax online account you are currently using, then yes you can.
To pay the TurboTax online account fees by credit card, without completing the 2021 return at this time, click on Tax Tools on the left side of the online program screen. Then click on Print Center. Then click on Print, save or preview this year's return. On the next page, to pay by credit card, click Pay Now. The next screen will show a review of your Fees, click on Continue. Complete the next screen to pay by credit card and click Continue.
If you mean paying for the federal taxes owed now before you file for an extension, then you can go to the IRS payment website for Direct Pay to make a payment for the 2021 taxes owed - https://www.irs.gov/payments
If you mean paying for the TurboTax online account you are currently using, then yes you can.
To pay the TurboTax online account fees by credit card, without completing the 2021 return at this time, click on Tax Tools on the left side of the online program screen. Then click on Print Center. Then click on Print, save or preview this year's return. On the next page, to pay by credit card, click Pay Now. The next screen will show a review of your Fees, click on Continue. Complete the next screen to pay by credit card and click Continue.
If you mean paying for the federal taxes owed now before you file for an extension, then you can go to the IRS payment website for Direct Pay to make a payment for the 2021 taxes owed - https://www.irs.gov/payments
If you owe taxes for 2021 you should pay before the April deadline, I think the 18th, even if you are going to file for an extension. This will avoid penalties and interest.