You should have received a Form 1099-R for the total amount of the IRA distribution. Enter the information from the 1099-R into TurboTax exactly as it appears on the 1099-R form, including the taxable amount. After you enter it and proceed through the interview it will ask you a series of questions about the IRA distribution. If the 1099-R has distribution code 7 or 4 in box 7, the IRA/SEP/SIMPLE box is checked on the 1099-R, and you are over 70½ years old, you will come to a screen that says "Transfer to Charity?" On that screen, if the entire distribution went to the charity, select "I had all of this distribution transferred to charity."
An RMD does not have to be taxable to satisfy the requirement to take the RMD. The IRA distribution will be shown on your tax return, which satisfies your RMD requirement. But it will not be included in your taxable income because you had it paid to the charity. If you are talking about 2021, the full amount of the distribution, from the 1099-R, will be included on Form 1040 line 4a. The taxable amount on line 4b will not include the amount that was sent to the charity. Next to line 4b there will be the notation QCD, which shows that part or all of the distribution was sent to charity.
