Die? How/when would I die?
Each creature has hit points (HP). When these reach 0, the player is on death's door. HP is lost from damage or from spells/effects that lower hitpoints, either directly or indirectly. HP is gained from healing, rest, potions, magical items/spells, or leveling. At zero hitpoints, the player loses consciousness and [except under certain circumstances] is said to be dying, and will slowly go into negative values of hitpoints unless healed/stabilized. When a person reaches the negative equivalent of their constitution score, they are dead dead. The higher the constitution, the longer it takes for them to die. [This also means that if, heaven forbid, someone's constitution score should somehow be lowered to zero, they would be dead, because the negative value of zero is zero.]