The word to can be used as a preposition. It gives the position of an object by telling direction.
Bob went to school.
I gave a card to Mom.
We are driving to Florida.
Janet went to the drugstore.
The word to can also be used as an infinitive verb – to eat, to run, to play.
It is time to eat.
Our dog likes to run.
I like to play at recess.
The word to can be used a a preposition and as an infinitive verb. You know the word to is a preposition when the word begins a phrase that shows position. A prepositional phrase never has a verb. to the store is a prepositional phrase. to play is an infinitive verb.
It’s your turn. Decide which of these sentences includes the word to as a preposition. Let’s go to the park. I like to play at the park. Did you pick the first sentence? Good for you!