How can I deduct extra federal income tax from a paycheck for one of my employees?

Hi genguys, 

Glad to have you join the Community. QuickBooks makes it easy for you to manage your payroll. It's essential you're able to get the advice you need on how to manage your employee taxes and I'll be happy to show you how. 

In order to edit the taxes on the paycheque, click on Payroll > click on the Run Payroll option > once the list showing your employees comes up, navigate to the employee in question and click on the 3 dots under the Actions column to Edit paycheque >  from here you'll see the type of taxes you can adjust for your employee. In case the tax option you're looking to adjust isn't showing, I recommend sending feedback about this to our product developers. To do this, click on the Gear icon and look for Feedback. 

Give this a try and let me know how you make out. I'll be one message away in case you need anything else. Otherwise, I wish you a great rest of the week. 🙂