Download and install the MediaTek (MTK) USB Drivers on your PC. Download the SP Flash Tool and the OPPO F3 Stock Firmware. Phase 2: Flashing Procedure
Once your Oppo F3 boots into Android 7.1.1 Nougat, open to ensure your services sync correctly. It is also recommended to update all your apps through the Google Play Store to prevent application crashes on the newer ColorOS version. oppo f3 nougat 711 official update download fix