Use it like an electrical box with blue LEDs. Press the green flag twice for the arrow to scroll properly. I can't help it, it's a layering glitch.
Remake of an older project I made on one of my first projects (check under MrT_Builder's profile (my old account that was hacked)). Please give me feedback of a comparison between the two after you've looked at both projects! Old project: https://scratch.mit.edu/projects/169190041/