Yes, the noun 'street' is a common noun, a general word for a public thoroughfare.A proper noun is the name of a specific person, place, or thing. A proper noun for the common noun 'street' is the name of a street or someone or something named Street. A proper noun is always capitalized.Examples of proper nouns for the common noun 'street' are:Della Street (Perry Mason's secretary)Wall Street, New York, NYBird Street Cafe, Oroville, CA