I'll gladly share some details with you about the Social Security tax rate.
The Social Security tax rate is already set automatically within the program. We're unable to see it in QuickBooks. Though, the current tax rate for both employers and employee is 6.2%.
If you need to check your payroll data, I'd recommend running the payroll reports in QuickBooks. This article can help you familiarize them: Run payroll reports.
I'm down to answer any other questions you might have regarding your payroll taxes. I can also help you out with any other processes in QuickBooks.