VS 2017 Beginner Need a Guide

what do i need to do so my output would be like this can help me please

this is my code

Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

Dim strLength As String = TextBox1.Text
MessageBox.Show("Output : " & strLength.Length.ToString)

End Sub
End Class

what do i need to do so my output would be like this can help me please

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