title: Open a workbook using FileDialog and manipulate it
body: <p>I found this code here on StackOverflow:</p>
  
  <pre><code>Dim fd As Office.FileDialog
  
      Set fd = Application.FileDialog(msoFileDialogFilePicker)
  
      With fd
  
          .AllowMultiSelect = False
          .Title = "Please select the file to kill his non colored cells"
          .Filters.Add "Excel", "*.xls"
          .Filters.Add "All", "*.*"
  
          If .Show = True Then
              txtFileName = .SelectedItems(1)
          End If
  
      End With
  </code></pre>
  
  <p>I know this code should select a file in <code>FileDialog</code>.
  However, once I have chosen the .xls file, how do I manipulate the file? In other words, where is my file object for me to manipulate?</p>
  
  <p>I would like someone to continue this code to make some simple manipulation on the workbook so I could learn how to do those simple things on a workbook that I opened.</p>