Schematic PDF for a board identified as MS-7420, variant N1, revision 0C, judging by the MSI-style number in the file name; no brand field is attached. The 1.18 MB document lays out the circuitry page by page, useful for tracking down power rail faults, reading the power sequencing logic and identifying component values on damaged areas. MSI prints these numbers on its PCBs, so confirm the exact variant and revision printed on the board, since a 0C sheet may differ from later production revisions.
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 @pepeelectronica. 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.