How to create a common property for two classes?

Question

Programming

Bottom line:
There is a room. The room has windows, doors, cutouts in the wall, etc. (let's call them elements).
Created two classes respectively:

class Room{}
class Element{}

The room and the element have standard parameters: Length, Width, Height.
Accordingly, the room object and the element object must have properties with parameters, let's say Dictionary:

class Room { public  Dictionary<string,double> Params {get;set;} }
class Element { public  Dictionary<string,double> Params {get;set;} }
Room room = new Room();
Element element = new Element();
room.Params["Width"]; 
element.Params["Width"];

The room contains many elements, let's say the List<> property How to create a common property of the standard Parameters (Params) for these two classes? If inheritance is applied, then an object of the Element class will also have a list of elements Elements: , which will be incorrect.
public List<Element> Elements {get;set;};
element.Elements[0]["Width"]

Answer 1

If I understand correctly, then you can make an Element class that will contain the width, height, length properties.
From this class, inherit the Room class and add List Elements