To become pro you will in nearly all cases need to be very aggressive and have inside out knowledge of the game.
to be succussful with aggression you need to be able to represent hands well when you dont have them and understand your own image in every hand and understand betting patterns and position in order too represent hand ranges
and to read hand ranges
(this will continuously change) so their is no quick fix you have to have the ability as reading a book wont last forever.
you also need an understanding of which players are capable of advanced exploits and which players are purely their to pay you off when you have a hand.
you need a solid ABC background, in which you understand position , equity, odds and statistics in order to meassure your ranges,
and you will need to most importantly comitt 100% into training and learning the game as in any proffessional game you cant expect to just learn one way of playing and make a career from that,
it involves creativity and alot of skill and everything you learn on here is just the basics you need to create an edge for yourself if you want to be better than the average cards chat / poker forum