How do you cope that the fact you might die one day

I’m 22 and I’m afraid of death, the fact that nobody knows what happens in the afterlife it’s frightening is it not?
Some people might think in their minds but you’re young! Death comes for everyone.
My mom died of breast cancer and I’m terrified that one day it might be too late for me or my sister to get it treated, I might’ve been little when that happened but I remember the times she was in pain, it’s heartbreaking. I’ve told my sister multiple times to get herself checked cause we both have double the chance of getting it but she always brushes me off saying why do you think that or I don’t have time.
Im scared, I don’t have insurance and I needed to withdraw all my 401k for an emergency.
I’m scared I won’t have enough money to cover for my future medical bills.
I live in the us so healthcare is literally disgusting here, and I’ve seen who easily doctors brush off symptoms until it’s too late.
(Sorry for the 1am rant)