This quest is fairly simple. You will have to learn all the three words of power of clear skies by looking at them for a while when the greybeards cats them on the ground. Use this shout to get rid of the deadly wind on the passage to the throat of the world. On the way there are a few enemies, but you can take care of them easily as they come at you one by one (it is a couple of ice wraiths and a snow troll). On the top of the mountain (the throat of the worl) you will find Paarthurnax who will give you directions towards the elder scroll.