A recurring cyclic theme I'm sure we all see, is someone with the Knack wants to get started in the embedded field. My recommendation for the first thing to start with is the book, for the long obsolete 68HC05, Understanding Small Microcontrollers by James M. Sibigtroth.
Which I'm sure many readers of this blog might find odd. Just because it is old doesn't mean it is still not educational. The book covers the fundamentals like computer numbers and other things that more experience authors gloss over. It is also free, a price a budding seven year old can afford, until someone can drive them to the library. Obviously lots of resources on Internet, but to me the best way for a young person to learn is with books, to spur the imignination.