Good day, akautokare.
You can add multiple users depends on what version you're using. You can check the comparison through this page: https://quickbooks.intuit.com/pricing/.
Here's how to add a user:
I've added this reference so you can check what are the different levels of access that you can give: Add and manage custom users.
If you face challenges while doing this, please let me know. I'll make sure to address them as soon as I can.