Well first you have to learn the Arduino programming language. And the stdlib.

They don't call it C++ because that sounds too difficult. But it's literally, not like a simplified subset that compiles into an IL using a formally proven tool, but as in literally compiled using GCC as, C++.

It's C++, and basically what Arduino gives you is

  int main() {
    setup();
    for(;;) loop();
  }

I'd assume the average user on HN should be able to figure it out pretty easily.

it's literally the hello world of micros. get an arduino, plug it into the usb, install the ide, new -> example -> 01. Blink. Press Run. Cool you have now blunk a led. Now use AI to draw the rest of the owl.

Good thing LLMs exist now