If you have multiple store, please setup your store list in Settings > Store.
For physical store, you will need to select one of the store when you install and setup your StoreApp on a tablet. Member operations will be reflected to this store for managing and tracking purpose. For example, when a member sign up, a note will be added that this member sign up at the selected store.
For online store, you must setup as "eCommerce" store before you can integrate it to Eber.
Provide necessary details to create your stores accordingly to complete the setup.