A Beamcore account is logged in in one place at a time: on one device in the app and in one browser in the web application. So every user needs their own account. This applies to everyone and you do not need to set anything up for it. The Beamcore interface is in Dutch, so button and menu names are shown in Dutch with a translation.
In the web application
If you log in in another browser or on another computer, you are logged out in the previous browser as soon as you click something there again. The login screen then shows the message Je bent uitgelogd (You have been logged out): your account has been logged in somewhere else. Log in again to continue working there; you are then logged out in the other place.
A page you open from the app does not count as a second place.
In the app
If you log in to the app on another device, you are logged out on the previous device and taken to the login screen there. Push notifications then only arrive on the device where you are logged in.
If several people work with the same account, create a separate account for each of them. See Inviting users.