Its b/c he is probably not using the work hawk to mean like, a bird. hawk has another definition "a person who aggressive of warlike policy" I'd have to see the sentence that comes before this but the poet is probably referring to something aggressive or warlike.
Well, usually most poetry doesn't use the word "the" in the poem. The reason is because it might sound too extra. Hope i got it correct! Enjoy the free answer!
Conceited means that someone is very proud or vain. The first one says that he communicates intimately with himself and when he agreed on something it was done.
