The file name indicates that this is the first part of a multi-part compressed archive. To use this file, you generally need to keep the following in mind:
You cannot open just "Part 1" on its own. You must have all parts (e.g., part1, part2, part3, etc.) in the same folder. When you extract "part1" using a tool like WinRAR or 7-Zip , the software automatically pulls data from the other parts to recreate the full .xci game file. Sonic Frontiers (XCI)(Asia).part1.rar
It looks like you are dealing with a specific split archive for on the Nintendo Switch. The file name indicates that this is the
An .XCI file is a "cartridge image" used by Nintendo Switch emulators (like Ryujinx or Yuzu) or on hacked consoles. Sonic Frontiers (XCI)(Asia).part1.rar