Nokia 2 archive of 4.35 MB; the name gives only the phone model and says nothing about whether it holds firmware, schematics or service documents, so the contents need checking after extraction. Phone service files of this size are typically schematics, a service manual or partial flashing data used for tracing charging or power faults or for recovering software. Inspect the extracted files and confirm that they match your handset variant, for example by its TA model code, before using them for diagnosis or flashing.
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 @SMART_PHONE_SCHEMATICS. 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.