The suggested available drive space during Windows Store installation is 60GB. Forza Support
Repacks usually compress the game files to reduce the download size, making it more accessible for users with slower internet connections. Forza Horizon 3 -DODI Repack-
While DODI is considered a "trusted" name in the scene (they do not bundle obvious malware), downloading from third-party torrent sites is risky. The suggested available drive space during Windows Store