What is the verb of exclaim?

Exclaim is already a verb. A verb is a Word that describes an action, or "a doing", Word.
Other verbs are exclaims, exclaiming and exclaimed, depending on the tense that you are writing in.

Some example sentences are:
"I need more chocolate drenched eggs!" I exclaim.
"I need more spicy marshmallows!" she exclaims.
She is exclaiming about needing all these weird foods.
"I am eating all these weird foods, think I might be pregnant!" she exclaimed.