I am making a program for Microsoft Flight Simulator X, and When you are in Multiplayer in most games there is a Chat room, or Chat Box. Do you think that there is any way I can reach maybe an API or possibly monitor the Screen so If someone types !Help in the chat box my bot would Respond like "Software by (whoever) other commands" stuff like that.
But I cant seem to find any info about API's in the Microsoft Flight Simulator X SDK about Multiplayer Chatbox or any multiplayer functions in that matter.

Any Help would be awesome. :)

Use the _TextChanged Event of the TextBox.

Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged
        With TextBox1 '// shorten typing.
            If .Text = "!Help" Then '// to not make it case sensitive, use ( If .Text = "!Help".ToLower Then ).
                .Text = "Software by (whoever) other commands" '// replace text.
                .SelectAll() '// select all text.
            End If
        End With
    End Sub