Octopath Traveler -nsp--jp--update 1.0.5-.rar File
This kind of file would typically be downloaded from the internet and then extracted (unpacked) using software capable of handling RAR files, such as WinRAR. After extraction, the update could be applied to the game on a Nintendo Switch, presumably through a specific process or menu option on the console, although the exact method might depend on how Square Enix intended for updates to be handled.
Without more information on the context in which this file was encountered, it's hard to provide further specifics on its use or implications. However, understanding the components of the filename can give insight into its purpose and handling. Octopath Traveler -NSP--JP--Update 1.0.5-.rar