A complete paraphrase of the this short poem could be the following:
He clasps the crag with crooked hands;
Close to the sun in lonely lands,
Ringed with the azure world, he stands.
There is a lone eagle on the top of a rock outcropping who is grabbing that rock with strong claws while he surveys the land. Because I am looking up at the eagle it appears very close to the sun overhead and the bright blue sky is glowing around him.
The wrinkled sea beneath him crawls:
He watches from his mountain walls,
And like a thunderbolt he falls.
From the eagles perspective up on the mountain wall it appears that the water down below is wrinkly as the waves wash to shore. Once he decides to move he takes off with the swiftness and power of a thunderbolt.
The poem does a masterful job of capturing the majestic beauty of an eagle in this setting. Tennyson uses a short iambic tetrameter line with a clear, strong rhyme scheme to unify each image, and he uses alliteration, assonance, consonance, imagery, and figurative language to create this vision.
Paraphrasing is when you put the poem into your own words
Eg:"He clasps the crag with crooked hands"
Could be Paraphrased into
The eagle stands on high grabbing the mountain rock
with it's claws etc.
I hope this helped ..Nicola :L