The "CIA" in the filename typically refers to a , which is the installation format for the Nintendo 3DS system. Suggested "Solid Paper" Guide for Using This File Preparation
: As this is "part1.rar," you must download all other required parts (part2, part3, etc.) from the same source.
: Place all parts in one folder and extract only the first part using a tool like 7-Zip or WinRAR . This will automatically merge them into a single .cia or .3ds file. Installation on Hardware (Nintendo 3DS)