The actual principal is simple, your classes have private properties which contain the thing, you use get/set on public properties and on the set you raise a property change event (that's declared via an interface).

WPF binds to those objects and when you change the thing via a public property the change notification is fired and the UI updates.

Docs you want are MVVM and particularly INotifyProperyChanged.

https://www.c-sharpcorner.com/article/explain-inotifypropert...