from 2006 - 2008 i played online poker and paid all my bills house car food. I had 50 sites with money on them. There were tough times though I had no choice was laid up medically. Had no other resources at the time. Its a tough road.
I would suggest you take time prove you can make enough before leaving job etc.. Also you have to have very tight bank roll management and other rules or you imho will fail miserabally.
I tell anyone ive ever met all dreams are possible ive ran own business been with millionaires when at one point i was on street. You really have to have life lessons people skills even in online poker. I can tell you I know people here in florida who made over 1 million before the poker doors pretty much shut with the govt intervention. I know of 2-3 of these guys who are now broke and going back to college.
These are guys that legit won 1 million dollars in poker in tournaments and had stats to show it. Why did they fail? To me they were not ready for it at that time and didnt have the full skills needed to run a business and keep the money they made or maturity etc..
Is a big decision yes can be done but plan it all. Make very stringent rules to follow. Plan each step take notes and dedicate what you can to it but also know you need absolutely need the other parts of life to meet with the poker world in order to be and maintain success.
Anyone can get lucky hit the lotto to maintain learn and develop and keep going is very very very hard. Most dont do it right is why you see poker players broke who had millions