Compressed RAR package for the Samsung SM-A125F, 1.80 MB, whose name gives the model code and nothing more about what is inside. Extract it with WinRAR or 7-Zip and check whether it holds schematic sheets, a component layout or other service pages. Such documentation helps a technician follow battery and charging paths, identify components around the SoC and PMIC, and measure test points during fault finding. Confirm the model code on the phone first, because Samsung uses suffix letters for regional versions.
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 @cyberlanelectonik. 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.