"Jenny told her friends that someone was coming over this afternoon." uses an indefinite pronoun, and, "Marcus told his parents that he would just drive himself to the game" uses a reflexive pronoun.
Explanation:
Indefinite pronouns are the ones that refer to things or people without saying directly who are they referring to, in the first sentence the indefinite pronoun is "someone"
Reflexive pronouns are the ones we use when the active person in the sentences is also the receiver of the action, in sentence two the reflexive pronoun is "himself"
