Pronouns are words we use in the place of a full noun.
We have both subject and object pronouns:
Use he/him to refer to men, and she/her to refer to women. When we are not sure if we are talking about a man or a woman we use they/them.
This is Jack. He’s my brother. I don’t think you have met him.
This is Angela. She’s my sister. Have you met her before?
Talk to a friend. Ask them to help you.
You could go to a doctor. They might help you.