To start, search for "TTGO_USB Virtual keyboard Demo" and go to the Github link. Install "arduino ide" and, if needed, the drivers. The "USB key" I received is detected as "Arduino Micro". After some tests and adding libraries to use an AZERTY keyboard, it works pretty well. The site https:**d4n5h.github.io*Duckuino (replace the * with /) is also very useful! ;-)