I'm not sure how to do this in TurboTax, but you can manually fill out a form and mail it to the IRS.
For details on this refer to https://www.irs.gov/forms-pubs/about-form-1040-es
This site includes a link to a Form 1099-ES PDF. Click that link.
The PDF includes instructions, a calculation worksheet, tax brackets and the form itself (on pages 9-11).
Print the form, fill it out, and send the money to the correct address.
Be sure to keep a record of your payment date and amount so you remember to report this on your 2022 tax return.
You may also want to investigate whether you want to pay estimated taxes to your State.
Lastly, next time, you can consider having taxes withheld, by your financial institution, from your conversion when you do your conversion. This will save you the trouble of filing the 1099-ES, but it will reduce the amount converted to your Roth IRA.
