Install a BitTorrent client such as qBittorrent, Transmission, or Deluge
Obtain a legal torrent file or magnet link for the content you want
Open the torrent file in your client or paste the magnet link into the client
Choose the download location and any file selection options
Start the download
Wait for the download to complete
Keep the client open if you want to continue sharing the file with others
Verify that the content is legal and that you have the right to download it