How to use setters in properites, for clarification

https://www.codecademy.com/courses/learn-c-sharp/lessons/csharp-interfaces/exercises/build-an-interface

Just so I am not confused, when a property has only a getter, but not a setter, that means noone with access to the property can set its value.

And if it has a private setter then only the property itself can give it a value.
But if it has just a setter, then it can only be set by the class it was defined in?( Or at least an instance of that class?)