Flashing firmware carries risks, including potential "bricking" of the device, and may void your warranty.
Before trying manual methods, check if an official update is available for your specific region: app on your phone. Scroll down and tap on Software Updates download file firmware update oppo f3 nougat work
Note: Always check the MD5 checksum if provided to ensure the download isn't corrupt. Flashing firmware carries risks
Look for the file on trusted forums like XDA or Oppo’s official support page for your model number (CPH1609). Avoid random “firmware download” sites. including potential "bricking" of the device
Confirm your device is the CPH1609 (OPPO F3) by going to Settings > About Phone . How to Install the Nougat Update (Manual Method)