Just a conversion. You should get a 1099R for it. It will be taxable. It is not a new contribution so don’t enter it under Deductions & Credits.
Enter a 1099R under
Federal Taxes
Wages & Income
Then scroll way down to Retirement Plans and Social Security
Then IRA, 401(k), Pension Plan Withdrawals (1099-R) – Click Start
After you enter the 1099R it will ask you some follow up questions.
Pick I moved it to another retirement account. Then it will ask if it was to a ROTH.
Then choose - I did a combination of rolling over, converting or cashing out the money
Then it will ask how much you converted to a ROTH
The whole gross amount (before taxes) is 100% taxable. Then you get credit for the taxes withheld on 1040 line 25b.