Sure, I can help you with that. Here are the steps on how to use hashtable in VB.NET:

1. Import the System.Collections.Hashtable namespace.
2. Create a new hashtable object.
3. Add key-value pairs to the hashtable.
4. Get the value associated with a key.
5. Remove a key-value pair from the hashtable.

Here is an example of how to use hashtable in VB.NET:

VB.Net

Imports System.Collections.Hashtable

Sub Main()
    ' Create a new hashtable object.
    Dim hashtable As New Hashtable()

    ' Add key-value pairs to the hashtable.
    hashtable.Add("key1", "value1")
    hashtable.Add("key2", "value2")

    ' Get the value associated with a key.
    Dim value As String = hashtable("key1")
    Console.WriteLine(value)

    ' Remove a key-value pair from the hashtable.
    hashtable.Remove("key1")

    ' Display the contents of the hashtable.
    Dim keys As ICollection = hashtable.Keys
    Dim key As String
    For Each key In keys
        Console.WriteLine(key & " = " & hashtable(key))
    Next
End Sub

This code will create a new hashtable object and add two key-value pairs to it. The code will then get the value associated with the key "key1" and display it on the console. The code will then remove the key-value pair associated with the key "key1" from the hashtable. Finally, the code will display the contents of the hashtable on the console.

The Hashtable class represents a collection of key-and-value pairs that are organized based on the hash code of the key. It uses the key to access the elements in the collection.

A hashtable is used when you need to access elements by using key, and you can identify a useful key value. Each item in the hashtable has a key/value pair. The key is used to access the items in the collection.

Module Module1
    Sub Main()
        Dim ht As Hashtable = New Hashtable()
        Dim k As String
        ht.Add("001", "anupam singh")
        ht.Add("002", "sunil kumar")
        ht.Add("003", "vinay pawe")
        ht.Add("004", "arjun singh")
        ht.Add("005", "Manish Mishra")
        ht.Add("006", "Manoj Panday")
        ht.Add("007", "Sohel khan")
        If (ht.ContainsValue("Shiv chand")) Then
            Console.WriteLine("This student name is already in the list")
        Else
            ht.Add("008", "Shiv chand")
        End If
        ' Get a collection of the keys. 
        Dim key As ICollection = ht.Keys
        For Each k In key
            Console.WriteLine(" {0} : {1}", k, ht(k))
        Next k
        Console.ReadKey()
    End Sub
End Module