This method is safer and more common for the F11 because TWRP support for MTK devices can be sporadic.
Before downloading anything, you must confirm your specific model number. The standard OPPO F11 usually carries the model number CPH1931 . Flashing files intended for the F11 Pro (CPH1969/1971) or the F11 (Pro) Marvel Edition can hard brick your device. oppo f11 root xda link
The modern standard for root, which involves patching the device's boot image. Risks and Considerations Rooting the This method is safer and more common for