My question is really basic but why are there 2 characters in a starter deck and how do i playthe seconde one or do i let5 it stay there or does it go in the deck im confused? and what is the pool?

Having the extra character in the deck can be useful because it has a 6 control check and a +0 mid block, so you can use it for blocking.

The card pool is where you put the cards you play during the turn.

sounds like a great game , i'm tempted .