To start winning the game you need to learn how to play it. That means you have to get good at recognising patterns in both the way you need to play situations, and the way opponents tend to bet in certain situations. Since SnGs and Ring are so different, and Limit and No Limit are so different the patterns you need to try and recognise are totally different in each. If you play a combination you are getting a whole load of contradictory information about how you should be playing in certain situations and that is not going to help you learn the game. It is better to focus on one type until you are at least half decent and then you can start spreading out a little.

In a ring game (certainly at low stakes) you win by literally waiting for premium hands. In a SnG when the blinds are high and when there are fewer players your definition of a good hand changes radically with people losing entire (short) stacks with middle pair. The end of a SnG is often about the big stacks bullying the small stacks with any 2 cards, and the small stacks waiting for any 2 high cards or any PP to go allin. Ring is never like this. I think it is better to focus on 1 game type or the other in the beggining. That doesnt mean you cant play any SnGs but it does mean that most of your poker time should be spent playing (and studying) your chosen game.