To answer your specific question:
If you have a good reason to display the whole text in textbox1, and the string you require is always the second line:
TextBox2.Text = Textbox1.Lines(1)
To get direct from the browser:
TextBox2.Text = WebBrowser1.Document.GetElementById("Text1").InnerText
But as the others have mentioned, there are probably better ways to accomplish your task. What exactly are you trying to do?