There are basically two classes of USB devices used by all FCs: All this assumes you have the correct drivers etc setup correctly, read further on for details. The Configuration tool should now erase the target and flash the selected firmware to your Flight controller. Leaving all options unchecked ** (defaults) press 'Flash firmware'.
Select the correct firmware hex-file matching your Flight Controller. Press the 'Load firmware ' button, you can now browse to the folder you have the local Betaflight firmware file. Press 'Load Firmware ', lower right part of the screen. Select Target and Version in the upper left corner. Using Betaflight Configurator, select the Firmware Flasher tab and select what firmware to flash in one of two different ways, online or local firmware.
Installing Betaflight How to install Betaflight firmware on your FC: