This is a PCB to assemble your own keyboard adapter to use one of the following keyboards:

Commodore 64 keyboard
Commodore 16 keyboard

with either Apple 1 / Replica 1 plus, Apple II, or Serial TTL (I.e. RC2014) system.

See the full project notes on the authors website: https://p-l4b.github.io/appledore/

I have contributed the C16 firmware to the authors site, and the RC2014 (TM) compatible firmware is on my github here:
https://github.com/Alex-Kw/c64-rc2014-Keyboard

NOT included are any parts with this listing. You will need to assemble it and select the correct firmware for your Arduino Nano.