Welcome to the Community, @carpentersbldg835. I'd be glad to assist with your inquiry about federal withholding taxes in QuickBooks Online Payroll.

Keep in mind that you can only pay federal withholding taxes after processing payroll in QuickBooks Online. To verify this, check your Subscriptions and billing to see if there's an active Payroll subscription.

Here's how:

1. Sign in to your QuickBooks Online account.
2. Go to the Gear icon then select Subscriptions and billing.
3. From there you can view your current subscription/s.

Next, is to check the Payroll menu to see if there's a running payroll.

If you don't have a payroll subscription set up and running on your account, I suggest to contact our QuickBooks Online Payroll Support for further assistance. They can securely access your account and provide help through screen-sharing session.

I’m adding this article for future reference. This resource provide an overview of payroll tax wage bases and limits. From there, you’ll see answers to common questions about tax forms and payments: Payroll tax wage bases and limits.

Feel free to leave a comment below if you have other concerns. I'll be around to guide and help you out. Take care and have a good one.