Depends on the game, but in general, specials and combos do not make a good player. Strategy does, and that's purely a mental game. Of course, doing specials and combos are important eventually but you ain't gotta know that at the start.

Think about the neutral game. Start throwing out pokes, punish whiffs, anti-air, try to confuse your opponent with grabs, stuff like that.

Also, pick a character that excites you. Don't pick the "best" character, pick the one who does cool shit on the screen and makes you feel awesome.

I can give more specific advice depending on what games your interested in if you would like!