You have to be running torrent client software on your computer, such as BitTorrent ( https://www.bittorrent.com/download.html ) . You then start the client software, go to File-Add Torrent, and the software takes over from there.
Get utorrent from utorrrent.com it's 500k large extra fast, after first launch utorrrent will ask you if you wan't to asosiate it with torrent file types click yes, and next all you have to do with your torrent is double click it.
At school and work, I use **broken link removed**, if your willing to throw a few bucks, you won't need any piece of software to run your torrent. Since it's run on there servers it fasts and without any router, port blocking issues!!