Should I mark a tax exemption fo social security and medicare if my employee pay his medicare?

Welcome to the Community, @usermurestaurantllc. I'll share some insights about setting your employee as tax-exempt in QuickBooks Online (QBO).

To verify if your employee is subject to these taxes, I recommend consulting with a tax professional or accountant for specific guidance tailored to your situation. 

Once verified, you can follow the steps below to mark your employee as exempt:
 

1. Go to Payroll, then Employees.
2. Choose your employee.
3. From Tax withholding, select Edit.
4. Select the applicable Federal W-4 form if prompted.
5. Under Tax exemptions, tick Social Security and Medicare.
   
   
    
6. When finished, tap Save.

For more information, check out this link: Exempt your employee from Federal or State Withholding.

I'm adding this article in case you want to learn how to exempt your company from sales tax and get refunded: Request sales tax exemption and refund.

If you've got additional questions about tax exemptions in QuickBooks, just leave a reply below. The Community is always around to help.