1. Open the Arduino IDE and navigate to File > Preferences.
2. In the “Additional Boards Manager URLs” field, paste the following URL:
3. http://arduino.esp8266.com/stable/package_esp8266com_index.json
4. Click “OK” and head to Tools > Board > Boards Manager. Search for “ESP8266” and install the package, which includes the Arduino core for ESP8266.
5. Now, go back to Tools > Board and select “Generic ESP8266 Module” from the list. This setup is compatible with various operating systems, including Windows, Linux, and Mac OS.
6. That’s it! Your IDE is now set up to flash ESP8266 code, and you’re just one step away from uploading your first ESP8266 Arduino sketch. Once the setup is complete, you can upload code to ESP8266 using the Arduino IDE.

On Linux, the device shows us as /dev/ttyUSB0