You should receive a Form 1099-R for the withdrawal in January or early February.  The taxes withheld will shown on the form.

To enter a form 1099-R -

• Click on Federal Taxes (Personal using Home and Business)
• Click on Wages and Income (Personal Income using Home and Business)
• Click on I'll choose what I work on (if shown)
• Scroll down to Retirement Plans and Social Security
• On IRA, 401(k), Pension Plan Withdrawals (1099-R), click the start or update button

Or enter 1099 r in the Search box located in the upper right of the program screen.  Click on Jump to 1099 r