It's a pleasure to have you in the Community today, @hshira. I'll share some details to help you apply for a state tax account number so you can proceed to run payroll in QuickBooks Online (QBO).
Know that you'll need to reach out to your state agency about this way, they can help you complete the application, and have it set up to make sure that you have an accurate state tax number. You can refer to this article on how you can access your state agency websites: Payroll Tax Compliance Links.
In addition, I've got you this article to help you run payroll in QBO: Create and run your payroll.
You can also refer to this page in case you'd like to add your employees' pay history: Add pay history to QuickBooks Online Payroll.
Thanks for dropping, @hshira. Feel free to leave a comment below if you have any follow up questions about this. You can also post here again if you need help performing specific tasks in QuickBooks. Rest assured, I've got you covered. Take care!