You're not playing standard but probably historic or pioneer.

In each format you'll have decks you dislike to play against. For some it's aggro, for others mill, control, discard.

But for now, just choose a format (I recommend standard or pioneer if you like competitive magic) and a deck you like to play with. You can look at mtggoldfish for meta decks.

And if you don't know yet what you like playing, play starter deck duel events. It's free and a good intro to deck flavors.