All operations that clients perform are assigned to a collection. A collection is nothing but a set of objects (devices, computers, AD groups, and AD users) meeting the configured requirements. To use these objects to create a collection, the administrator first needs to create these from the console or configure the server in such a way that it will find the endpoints and save them in the database.
The database of the ConfigMgr server has nothing in common with the AD database. If an object is deleted in the ConfigMgr console, it will still remain in the AD database.
After installing the server, in the console, under Assets and Compliance\Devices, only devices with a ConfigMgr server role are visible. Assets and Compliance\Users, also, won't contain any objects.
The ConfigMgr server discovers objects based on built-in methods. Related to types of Active...