He had access to very good schooling in his childhood and free time to pursue his interests (computer programming). This was pure luck and critically important in forming who he is today.
He was able to obtain Canadian citizenship through his mother. This was pure luck and was very important when he emigrated to the US.
"Notable alumni includes two Nobel Prize laureates, 18 Rhodes scholars, eight Supreme Court judges, intellectuals and sportsmen"
His father owned several businesses, mines, etc.
1) What sort of luck comes your way? 2) Are you able to take advantage of the good luck and minimize the effects of bad luck?
If i'd had the exact same lucky breaks as Elon Musk I would not have been as successful, because I'm not as good at step 2 as he is.