Find Port on MAC

ls /dev/tty.*

Install Firmware

The first thing to do is download the most recent MicroPython firmware .bin file to load onto your ESP8266 device. You can download it from the MicroPython downloads page. 

Erase Flash

esptool.py --port /dev/tty.usbserial-14220 erase_flash

Flash Firmware

esptool.py --port /dev/tty.usbserial-14220 --baud 460800 write_flash --flash_size=detect -fm dout 0 esp8266-20220618-v1.19.1.bin