Get a breadboard. Get a bunch of wire for it. And do small projects with the breadboard in a controller. It's fun to move the wires around. You can even build a tiny 8-bit computer with a breadboard. And have a do things like output of display. It's very tactile and hands-on. Excellent visual. There's excellent YouTube tutorials up there for breadboard projects.
https://www.youtube.com/channel/UCS0N5baNlQWJCUrhCEo8WlA
This guy has some excellent breadboard projects. Find an easy one. And do it together with your child