Hi there, setesting.
Our standard license agreement requires separate QuickBooks licenses for each person who uses the software. If you install QuickBooks in two or three computers, you'll need to get additional licenses. This allows multi-users to access QuickBooks simultaneously on their computers.
You can check out this article for more details on how to add user license: Add a user license to your QuickBooks software.
If you don't want to add another user license, you can use the Accountant's Copy feature. This allows accountants and clients to work on a company file at the same time.
To learn more about the Accountant's Copy, you can refer to this article: Use the Accountant's Copy.
Feel free to reply to this thread if you have more questions in QuickBooks. I'm here to help.