Fourth file in the Samsung SM-J250F (Galaxy J2 Pro) schematic series, a compact 212 KB PDF that is likely just a few pages or a single block diagram. The name does not say which circuits it shows, so open it to see the contents. Smartphone schematic pages are used for following power rails, checking component values and locating parts while diagnosing a dead or partially working board. Use it with the other numbered parts and check that the board revision matches.
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 @mobileshematic. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.