Adding ListCollectionItems And Referencing Items

I'm trying to add an item to my object's List(Of, and reference the List(Of using the same property, just like how a ListItemCollection works.

In the second line you are referencing the "Items" property of a ListBox instance called test. That property points to a ListItemCollection, and in the ListItemCollection is the "Add" function. I call the Add function twice.

Dim test As New ListBox
test.Items.Add("item1")
test.Items.Add("item2")
For Each item As ListItem In test.Items
Response.Write(item.Text)
Next

Then in the loop I call "test.Items". This is what i'm trying to figure how to replicate that for my own class. I'm obviously missing something big here, but how can the test.Items property return the ListItemCollection that has the Add function, and returns a list of items that are in the collection like in the loop?

How do i structure my class(es) to do these functions:

myInstance.Items.Add(obj)
For Each obj in myInstance.Items
Next