Officially, you should support the filmmakers by renting or buying the film legally. But unofficially, the "Train to Busan Internet Archive" phenomenon proves that in the digital age, once a piece of art captures the public’s imagination, it is very, very hard to stop it from spreading—even if it has to crawl through a digital archive to find its audience.
But for a growing number of cinephiles, archivists, and budget-conscious viewers, the movie has found a second life in a surprising place: the . train to busan internet archive
That being said, if you're interested in exploring more films like "Train to Busan" or discovering new indie productions, the Internet Archive is an excellent resource. You can browse through their extensive collection of: Officially, you should support the filmmakers by renting