I'm not sure if your asking for yourself or for your grandkids. As I don't know much how the minds of kids work, I will give my view for 'yourself'.
From a software perspective, I assume that you're familiar with javascript. Think about how you learned that; the same will apply in the Arduino world. C/C++ and the Arduino specific functions need to be learned.
I started C approximately 30 years ago with TurboC on the PC. I had a book and followed examples. The IDE had a built-in help and if code contained a function that I did not know, I could place the cursor on it and press <F1> to get help on it. That help sometimes also contained another function that I did not know and again I could place the cursor on it and press F1>.
What makes Arduino easy (beginner friendly) in my opinion is that you don't have to worry about the intrinsics of compiling (creating so-called object code) and linking (joining the different object codes together).
From a hardware perspective, you don't have to design your own system, nowadays you simply connect modules that you need; it is mostly plug-and-learn-to-play. At occasion you might blow something up due to incorrect wiring or not paying attention to details that you don't know about.