QuickBooks POS Integration is Store Manager addon, that means, that it is a part of Store Manager (it is already built-in the software) and should be registered with a separate license key. So in order to use the addon you have to install and register Store Manager and set up all required settings first.
In order to start using the QuickBooks POS Integration addon you have to go through the following steps:
7. Check your products on QuickBooks POS.