To do lights is a little hard but I did it to my ddr solo pad so more or less:

code https://github.com/StarlightLumi/DanceCtl

you need 12v leds got mine from https://ddrpad.com/

Arduino Leonard

Breadboard

12v power supply (I used a wii power brick I got for free)

4 mosfet's https://www.amazon.com/Anmbest-High-Power-Adjustment-Electronic-Brightness/dp/B07NWD8W26/ref=mp_s_a_1_6?crid=B01KAY4YS8ZV&keywords=mosfet&qid=1639499644&sprefix=mosefets%2Caps%2C215&sr=8-6

Wire up Arduino like this pin 6 up, pin 7 right, pin 8 down pin 9 left And ground for the common wire going to all of them.

Then for lights when you step on up it will send 5v to pin 2. But you want 12v to power light so you have to run pin 2 and ground to mofete trigger side. Run 12v power supply to mosfet input and run wires from output to lights. Its harder to explain then it is to do. I will make a drawing for you and send it

After much googling I ended up ordering some of these

https://www.amazon.com/gp/aw/d/B07NWD8W26?ref=ppx_pt2_mob_b_prod_image

Also someone over in /r/Arduino suggested just slapping a 10k resistor between the Arduino gpio pin and the button signal line. No MOSFETs or transistors needed apparently.