
Samsung Galaxy Note5
The latest firmware for Samsung Galaxy Note5 (SM-N920P) is N920PVPS3DRH1 with Android 7.0 (Nougat), released on August 1, 2018 for 2 regions (CSC). Every official firmware build for SM-N920P, newest first: one row per build with all regions (CSC) that received it.
Each firmware build has its own page at https://samfirm.shop/build/{PDA}, where {PDA} is the build number from the list above. Example: https://samfirm.shop/build/N920PVPS3DRH1
SM-N920P started on Android 5 and has received 2 major Android upgrades; it now runs Android 7.0 (Nougat). The newest build, N920PVPS3DRH1, was released on August 1, 2018. No new build has appeared for 100 months, so regular updates for this model have most likely ended.
Specifications of SM-N920, a regional variant of the same device. Chipset and SIM lines are left out: they can differ by region.

SM-N920AZW

SM-N930V

SM-N910V

SM-N915V

SM-N916S
The newest firmware for SM-N920P runs Android 7.0 (Nougat): build N920PVPS3DRH1, released on August 1, 2018.
The latest build for SM-N920P, N920PVPS3DRH1, was released on August 1, 2018 (8 years ago).
SM-N920P has had no new firmware for 100 months, so regular updates have most likely ended.
Yes, all firmware files for SM-N920P are 100% official, original, and obtained directly from Samsung servers.
To flash SM-N920P, you need to download the appropriate firmware, put your device into Download Mode, and use the Odin tool to load the BL, AP, CP, and CSC files.
Downgrading is only possible if the bootloader version (binary bit) of the old firmware matches the current one. Always check the binary version before flashing SM-N920P.