You may have heard the adage that the "house always has the advantage." Video poker is an exception to that rule. If you look for the most liberal pay tables, and play them properly, you can have a thin advantage. Some pay tables, which are slightly in the machine's favor, can return over 100%, if you factor in incentives such as cash back, free play, mailers, and other comps.
Online gambling is largely unregulated in the U.S. That means the casinos serving U.S. players generally don't answer to anyone. If you have a problem with a casino (like they won't pay you), then you're usually out of luck. I can't count how many players have written to ask me for help because they didn't get paid by some other casino. (Not that I helped them—if a dodgy casino won't pay you then you're on your own.)
Video poker is a very volatile game, about four times as much as blackjack. In any form of gambling, short-term results mostly depend on normal mathematical randomness (what some might call luck). However, in the long run, results mostly depend on skill. If you play a game with a return of 100.76% perfectly, that does not mean that you will have a 0.76% profit every time you play. The 100.76% is an EXPECTED return. Much in the same way, if you flip a coin ten million times, the expected number of tails will be five million, but it is unlikely you will hit five million on the nose. Actual results will vary significantly from expectations, but the more you play, the closer your actual return percentage will get to the expected return.