The site points your torrent client (like qBittorrent) toward a "tracker" or uses a Distributed Hash Table (DHT) to find other users.
Libri gratis, le biblioteche pirata si spostano sul dark web - Wired Sito torrent
Reputable sites often have a comment section. If a file has zero seeds or the comments warn of malware, avoid it. The site points your torrent client (like qBittorrent)