ESP8266 does not response
These tutorials often forget to tell you to place the ATmega chip in RESET if you want it to function as a UART-USB-pass-through. This is easily done by connecting the RESET pin to GND with a jumper. Also consider powering the ESP from a more powerful source, like the Arduino 5V pin through an LM1117 regulator. Don't forget to set your Serial Monitor to Both NL &amp; CR. Use a voltage divider between the Arduino's RX pin and that of the ESP, to reduce the 5V signals to 3.3V.