To still answer your question. Above code does not create an object of the given class. You can consider class as a template as to what your object will look like. Using this class you can create an object in some other function (where you wish to use it) . And the function where you create the object will then invoke display() method on that object.
Dim Adapter As New OleDbDataAdapter
Dim Command As New OleDbCommand
Dim xFrom As String = dtpFrom.Value.ToString.Substring(0, dtpFrom.Value.ToString.IndexOf(" "))
Dim xTo As String = dtpTo.Value.ToString.Substring(0, dtpTo.Value.ToString.IndexOf(" "))
sqlQuery = MainQuery ...