Answer:
To get to the grocery store, walk or drive north on Main Street
Step-by-step explanation:
In the sentence, “north” should not be capitalized because it acts as an adverb that indicate direction. However, when this word acts as a noun that refers to specific regions or are part of a name (e.g.: “in the North” and “the North Coast”), it should be capitalized. As for the word “on,” it is a preposition, and prepositions are never to be capitalized. Lastly, “Main Street” is a proper noun, that is, a noun that names an specific thing or person, and as all proper nouns, it should be capitalized.