What is a supplemental IRA Account? You can not transfer a RMD required minimum distribution to another IRA. You have to take it out. You should have received a 1099R from each account you took a distribution.
The easiest way to get to the 1099-R entry screen is to simply search for 1099-R (upper- or lower-case, with or without the dash) in your TurboTax program and then click the "Jump to" link in the search results.
Enter a 1099R under
Federal Taxes on the left side
Wages & Income at the top
Then scroll way down to Retirement Plans and Social Security,
Then IRA, 401(k), Pension Plans (1099R) - click Start or Revisit
@dmertz
