You are 20 years old.
According to the Social Security Adminstration, if you are male you have a .1% chance of dying in the next year. But you will probably live another 57 years.
If you are female, you'll probably live a little longer: 57 more years. There is still a .1% chance you'll die in the next year though.
Anyway, you are probably about 30% of your life left. Have fun with it.