Go back to the 1099-R interview - do a Search for 1099-r and click on the jump-to link.
In the 1099-R interview, if you are 70 1/2 or older, on a screen subsequent to entering the 1099-R you will be asked if part or all of this distribution was an RMD. Answer "Yes", if that is the case.
On the screen after asking the RMD amounts, you will be asked if any of the RMD was transferred to a charity. If you answer all or part, then enter the part, TurboTax will remove the all or part QCD amount from line 4b on the 1040.
Do that and come back if you have any questions.