Good day, Pooja.
I'd be happy to provide details about the licenses.
If you're trying to add more users in QuickBooks Online and see the user limit message, then you might want to check you plan's user limit here: How many users can I set up?
You can delete the ones you don't want to grant access in order to add the new users.
Feel free to open this link for reference: Add and manage users in QuickBooks Online.
If you're referring to the license seats in QuickBooks Desktop, please see: Add a user license to your QuickBooks software. Otherwise, contact our Customer Care Team for further assistance:
Please let me know if you need something else. I'll be right here to provide details and instructions. Have a great day ahead!