First things first:
An object is just an instantiation of a class. Think of a class such as Car, in the car you can have multiple methods, properties (velocity, number of seats, horsepower), etc. A constructor is basically what you put near the beginning of a class in order to initialize it and setup the class object properly. It is called when a new object of that class is created.
So lets say you want to declare a new object from the class Car, let's call it a Camry. You declare it as such: Car Camry = new Car();
Now in that same Car class, let's say there's a constructor. And this constructor is used to setup a set number of properties (number of seats, car length, etc), and attach methods to be used (such as a method called TradeInValue(), which calculates trade in value based on given parameters). Also, in the real world, sometimes certain methods have to be initialized in order, otherwise it does not work properly (take Windows Forms for example). So the constructor's job is to just do a bunch of things when an object of that class is declared/used.
I mistook StashInventory to be a property, my mistake. If you wanted to create a new object from the StashInventory class, try this: StashInventory myInventory = new Loki.Game.Inventory.StashInventory();
Also, you can declare common namespaces you'll be using at the top of the source code, that way you can eliminate Loki.Game.Inventory, since it's already declared above, and just go with : StashInventory myInventory = new StashInventory();
Also, you're far from being dumb. When I first started learning C#, I was far behind what you are doing now. Just keep going to StackOverflow and Microsoft's tutorials, they'll help you out big time. I have only been doing C# for a short while now, so I might not be explaining things properly, and hopefully people on here can correct me when I am wrong

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