Since the FLY_CDY_V2 STM32 board comes without any firmware installed, I made a simple link for you to download and extract everything you need to a 2-16GB microSDcard.
Just download, extract, burn as-is to SD and plug it in the board, fire the board up and all works!
Make sure you follow the guideline HERE for getting attached to the board via wifi by using a USB cable and YAT terminal on your PC to get the home wifi SSID and Password programmed to ROM into the board, AFTER you installed firmware by putting in the SDcard and firing it up.
The settings in config.g at the SDcard are made for a Cartesian XYZ machine with triple extruder. This can all be changed to fit your build in config.g.
For a delta, use THIS DUET2wifi DELTA config.g and change the pin_name of bed heater according to the FLY_CDY_V2 name convention (thus: use bed instead of bed_heater).
For more info about the board and connecting to the electronics, steppers, endstops, filament sensors, BLTouch, Neopixels etcetera go HERE
Please donate $1 to my paypal account if you use (parts of) my developed materials so I can continue to share nice stuff for you to download