I'm Nobody! Who are you?
Are you -- Nobody -- Too?
Then there's a pair of us!
Don't tell! they'd advertise -- you know!
How dreary -- to be -- Somebody!
How public -- like a Frog --
To tell one's name -- the livelong June --
To an admiring Bog!
-Emily Dickinson
>is there assonance in this poem?
Not much, no. 'Who are you' would be one example, though. That is, repeated vowel sounds nearby one other.
>also what is consonance?
Repeated consonant sounds nearby each other, usually at the end (but also in the middle) of words. Compare alliteration - repeated consonant sounds at the beginning of nearby words.