Service archive for the Lenovo IdeaPad 3 15ITL6 built on motherboard NM-D471, revision 2.0, packed as a 12 MB RAR. The NM-xxxx numbering belongs to LCFC, the Lenovo-owned ODM, so expect LCFC-style schematic pages and net names. Typical contents of such a package are a schematic PDF and possibly a boardview, used for tracing power rails, finding test points and chasing shorts. Extract it with WinRAR or 7-Zip and confirm that the NM-D471 marking and revision printed on the PCB match before trusting the values.
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 @ShareMan_Electronic_Files. 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.