In the Arduino IDE, go to Sketch > Include Library > Add .ZIP Library. Select the file you just downloaded. Configuring Your Environment
Board: Select your specific model (e.g., NodeMCU 1.0 or Generic ESP8266 Module). download arduino esp8266 library
Additional Boards Manager URLs: Look for this field and paste the following URL: http://esp8266.com . If you already have other URLs there, separate them with a comma. Open Board Manager: Go to Tools > Board > Boards Manager. In the Arduino IDE, go to Sketch > Include Library > Add