What is a noun phrase?

A group of words which does the work of a noun is a noun phrase.

The boy wants to go to school.

"To go to school" is the object of the verb "wants". Hence it is a noun phrase. The phrase "to go to school" performs the work of a noun. It answers the question "What does the boy want?".

 If you have any other query, we would request you to post again. We will be happy to help you.