Most famously, Doug Gilmour wore #93. He is retired.
Yes, a player can wear any number they choose, provided they are the only member of their team that has it and the number is clearly defined on their unifrom. It is a number normally used by goalkeepers only, but many of these choose (or are given) other numbers, so it opens up the opportunity for their teammates.
YES A PLAYER IN THE LAKERS TEAM WEAR NUMBER 56
Randy Kyle
Number 63 is a rare jersey number for the sport of hockey. No goalie has every worn the number, but stars such as Brad Marchand have.
Mike Nugent on the Jets
jared allen minnesota vikings
Vince Papale
Goalies can wear any number but it is most common for them to wear the number 1.
Steven hampton
cassano fellipe some other goons
No, Hockey players require no education because, with any intellect, they would choose another career.