Most people I know who have got into that line of flying have been one of:-
(1) Qualified Engineers who work for companies (or are associated with voluntary organisations) operating such aircraft, and are also capable pilots in their own right.
(2) Ex-military who got to know the right people.
(3) Rich with time on their hands.
Your best bet is to try and get yourself into one of these categories. I've been trying to achieve (3) for years, but failed dismally.
And lets be honest, there's nothing wrong with playing computer games, but no amount of experience in that direction is going to get you into the cockpit of a real Spitfire.
G