There are a lot of "learning" videos, articles, tutorials etc all over the internet... If you think you are better cashgame player then try cashgame, If you feel better in tournaments/SNG, then try them. Read something about bankroll management first! its very important to not play on higher stakes than you should play.
You should have at least 100 BB in cashgame or 50-100 buyins in SNG/tourneys I guess.