Inside the box you will have two starter decks and four reward packs which gives you plenty of characters to start with. You will want more though, so make sure you check out all of the Shimmering Skies cards which include super rare legendary and (if you can find them) enchanted cards which have super cool designs. Enchanted cards are super hard to find but ive managed to pull two from booster decks that I have purchased. 

If you want to start your Lorcana journey, then the Gateway set if the best way to begin and you can build your skills from here. I recommend Disney Lorcana to anyone. It's a super cool game to play, super fun and totally addictive!