if they are the same files that are available for download via torrent, etc, then you can just make sure the file names match and that they are the same file size (meaning they are the same files) as the ones in the torrent, and then make sure the directory structure matches that of the torrent, and then you can start seeding the torrent, or at least become a peer for the parts of the torrent you do have which means people can still download from you.
This way, you are sharing the files like you wanted, but people will also download it faster because other people will be doing the same thing.