RAR archive of 1.16 MB whose name only says MI 10 s, presumably referring to a Xiaomi Mi 10S phone, with no indication of the document type inside. It could hold a schematic, a layout or service material, so open it and check the contents before use. For phone repair, such packs typically support tracing power rails, finding test points and identifying components around a short. Confirm the board version printed on the PCB matches the material before relying on it.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @mischematic. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.
7-ZipWinRARThe Unarchiver (macOS)