The Legend of Zelda: The War for Hyrule is a Zelda game for the Wii U and Shooting Star, the game takes place many years before the first official game in the timeline (Skyward Sword).
A Brand New Discovery
Many many years ago...three godesses came and used their powers to make the world, these godesses were known as Din, Farore and Nayru, after they finished they left the world but left their powers on a powerful sacred relic known as the Tri-Force.
Sometime after that, the humans came...they slowly evolved and learned until eventually they became what they are now...however, while the humans did evolve for good and became smarter, they also learned many bad things, such as hatred, jealousy and the desire to be superior, this caused battles and wars as they evolved.
Right now, we see the land of Shime, where a young royal soldier-in-training named Link resides, he is informed by one of the most experienced soldiers that the king has been recently called to an important meeting with the other kingdoms and that they must be ready to protect him and his daughter, "Zelda", Link agrees but the soldier still thinks he should test him, leading him to a short training course.
Cut to some time after and it's time for the meeting, after the rulers enter the meeting room Link can't help to overhear them and listens to the conversation, apparently a brand new batch of land has been found and the kingdoms have been discussing for some time now about who will get it, after overhearing a bit, another guard catches him and tells him to go investigate some weird noises outside, they do so and find some bandits which try stealing some money, they fight them but when they go back they overhear some loud shouting inside ending with the king of the Gerudos, "Gann", bursting out of the door followed by the others, the king then tells Link to be careful, as Shime is most probably going to end up caught up in a war.
This game plays like a 3D Zelda game, the perspective is behind Link but sometimes changes depending on the location, you can use your sword to fight against enemies but if you want more precision you can lock onto them with "L-Targeting" which you can also use to lock onto other things. Apart from his sword Link can also use other items and even pick up and temporarily use an enemy's weapon (though they break after using them enough times).
The game allows more freedom than before, allowing you to take on certain dungeons on whatever order you want and allowing you to traverse through the kingdoms as you please, sometimes the game will allow you to make small choices that affect gameplay and story slightly (which item yuo get, which dungeon you take, who you fight, etc).