1. Download and install the Arduino IDE.
  2. Start the Arduino IDE, go to File > Preferences.
  3. At Additional Board Manager ULRs enter You can add multiple URLs, separating them with commas.
  4. Go to Tools > Board > Board Manager, search for wifi duck and install WiFi Duck AVR Boards and WiFi Duck ESP8266 Boards.
  5. Download and extract this repository or git clone it.

If you can’t find the COM port of ESP8266 board, then you’re probably missing the right drivers. Here are links to drivers of the 2 most used UART chips on ESP8266 development boards: