This is a little difficult to find a "nice" solution for, as the WebBrowser control does not expose KeyDown, or KeyPress events.
It does expose PreviewKeyDown though, and that should work (but you may need to fine tune it a bit)
Handle the event, and call the SendKeys.Send method:
SendKeys.Send("Hello");
Be aware this probably will not work on your system: Because your activation sequence includes the CTRL key, there is a very, very good chance that this will be interpreted as CTRL+h, CTRL+e, CTRL+l...