To explore or extract CPK files—a proprietary archive format developed by and commonly used in games like Pro Evolution Soccer (PES) or Naruto —you can use several specialized third-party tools. Recommended CPK File Explorer Tools
To a mod, place the .cpk file in the game's download folder and use a tool like the DpFileList Generator to activate it. download cpk file explorer link
: A more general Windows utility that supports CPK files (Sega FILM Video format) among many other extensions. To explore or extract CPK files—a proprietary archive
Guide :: How to extract the files from the game! - Steam Community download cpk file explorer link