Nope, only enter it when you enter the 1099R. Then it will be deducted from your IRA distribution and you can’t deduct it again. Actually it’s better to have it deducted from your IRA distribution (called above the line) instead of taking a Schedule A deduction for it especially if the Standard Deduction is more than your itemized deductions.
A QCD won’t show up as income on 1040 line 4b so it will reduce your taxable income. IRA QCD should be 0 taxable on 1040 line 4b and QCD written by it. Unless you have other 1099R taxable amounts on 4b.
