Arduino is a open-source platform, containing both hardware(Arduino Board) and software(Arduino IDE).Arduino allows us to easily design and build our own objects. Arduino uses the C++ programming Language. This part of the module was quite easy for me to learn as I have previous experience.
Below is a circuit to test input and outputs. Using tinkercard, I could easily test out different circuits with different inputs. In this case, I used 4 buttons, each controlling one led when pressed.