I guess I would love to do it, it's (I know it will sound like a cliche) to run and tell all the people I love and those who do not, fellow friends, enemies, brothers and opponents, that really should die happy, that do not feel bad , let go of the guilt, and forgive all those who bothered you so much, let go of the pain, the bitterness in your heart, who smile at those people who never smiled at you the most, because of silly conflicts. Don't feel sad, don't try to repent of everything you have done: because everything meant learning, at the end of the day.

Let them try to listen to some song that makes them happy, or go somewhere that makes them feel like ... as in their home, as in those spaces of childhood happiness, that even if the world ends or not, those moments will not come back, Well, even if you had a bad childhood, you never really went away sad at all.
I would tell them not to be afraid either, because ...

"For a well-prepared mind, death is only the next great adventure"
- Albus Dumbledore