When your child reads at home have a conversation with them about what they read. Ask them who told the story and what clues from the text helped them to know.
Talk with your child about how most stories are told in the first person point of view (a character in the story is telling the story) or the third person point of view (a narrator is telling the story).
Some clues you can tell your child to look for in the text when they are trying to determine who is telling the story are pronouns. Is the story using I, me, and we a lot? Or is it always she, he, and they?
At the end of a reading session have your child change the point of view of what they read. Ask them to retell you a part in the book if it had been told in the point of view of a character or a different character.
Television shows and movies always have a point of view as well. Ask your child whose point of view their favorite television show is told from.