The way I see it is, there are only three games offered by the casino, that you can beat. Blackjack-Poker-Sports Betting
IF, you are good enough. To get "good enough", you will have to devote a lot of time and energy, to whichever one you chose.
Pick "one", the one that you are most interested in, and stick with it. All will take a great deal of time to learn. Realize that most who try any of these, will fail.
Trying to play more than one, is a mistake, for most people.
If you HAD to play Tiger Woods a game for $1000, but you had the choice of games, bowling or pool, would be a better choice than golf.
O.K., how long will it take, a few weeks, or months, or years ?
The answer--A LIFETIME, you will still be learning,(at least you should be) when you kick the bucket. You will get good, but you will never know all there is, to any of them.
People learn at a different rate. To some, it will come much easier, than to some others. Some will never be able to do it. Some that can do it, will decide it's not worth the effort.
Take your pick and stick with it. If it's BJ, see you at the tables. If it's one of the other two, see you at the casino. If it's none of the big three, see you at the ATM......