Look at these sentences: I do not like asparagus. Dad will not help me. Sue did not go to school.
In each sentence, the word not sits between the helping verb and the main verb.
do not like – the verb is do like
will not help – the verb is will help
did not go – the verb is did go
In each sentence, the word not is an adverb modifying the action verb.
Sometimes not is combined with the verb and shortened into a contraction.
I don’t like asparagus. The contraction don’t is actually do not.
Dad won’t help me. The contraction won’t is actually will not.
Sue didn’t go to school. The contraction didn’t is actually did not.
The word not is an adverb. The adverb not modifies an action verb by negating the action. If you use a contraction with n’t, you have actually added the adverb not to the helping verb.