Will a person who died at the age of 17 be punished for the insults and curses that he uttered, and is it true that whoever dies before the age of twenty will not be punished?

Whoever reaches the age of legal accountability (seventeen years old) and is sane, becomes responsible for their lawful actions. Cursing and reviling are serious slips of the tongue, and a major sin if directed at someone who does not deserve it. Good deeds efface evil deeds, and whoever dies without associating partners with Allah will enter Paradise. One should prepare for death by performing righteous deeds.