Hello,
> to enter the web page
Do you mean : go to TvHeadend interface (
http://ip_of_tvheadend_backend:9981) ?
ip_of_tvheadend_backend = localhost on the machine (with the adaptater connected on).
> Tv Adapter list is empty
Are you sure TvHeadend recognized your adaptater ?
If you are under Ubuntu:
You can install Kaffeine ($ sudo apt-get install kaffeine). If Kaffeine can't see any adaptater : your adaptater is not correctly configure in your system.
What is your adaptater ? ...