It makes sense that the June contracts are more expensive because you are buying an extra 3 months of time in which to be right. The more time you buy, the more time premium you are going to pay.
I would strongly suggest you visit this website and complete most of the courses before actually trading any options. I will link you directly to the pricing piece, but please use the whole site. It does a much better job of explaining options than anybody on this board (no offense to anybody else):