Yep, the gods of Tamriel are at war with each other for some reason or other (perhaps because you killed Alduin?) and you must choose whose champion you will be. First, there will be the issues involved. One set of gods is on one side of some issue or other, while the other gods are on the other side. So there would be god-teams. So you'd have to decide which side you wanted to fight for. Then you'd have to pick the god or daedra that you want to fight for, to become their champion. When you become their champion, they bestow all sorts of boons on you and powers of various kinds.
Then you lead the people of Tamriel into a giant war, because the gods don't fight themselves, but through their armies and champions. And the other side will of course have their own champion, who will lead their armies against yours.
As you progress and win battles, the other gods on your side will perhaps add to your powers or give you tokens of some kind.
And when the war is over, when you've finally won - you ascend and become a god(ess), just like Talos.