Archive named after the Samsung SM-J720F, the Galaxy J7 Duo model code, 4.16 MB in ZIP form; the name does not reveal whether it holds firmware, schematics or layout files. Packages keyed to an exact model code are convenient because the F suffix denotes a specific regional variant. Extract it and check the contents. If it is firmware, flash it only to a device reporting the same model code; if it is service documentation, match the PCB revision before using it for tracing.
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 @Schematics_Mobile. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.
Built-in OS tools7-Zip