As you know ESP8266 is a good modul for your IoT projects. First of all it is cheap and very powerfull. You can write code for it with Arduino IDE. It is easy to use and programing. But it is hard sometimes when you want to upload your sketch to ESP8266. Becaus ESP8266 comes with default mode only read. If you want to write any sketch to ESP8266 you have to connect GPIO0 pin with GND pin.
After that you can upload your any sketch to ESP8266. You can wath my video as below. Hope you enjoy this post. Don’t forget to subscribe my youtube channel and blog. Have a good day.