shit nigga

When you die, you will decompose into the ground. You'll turn into atoms and whatnot that spread throughout the ground as you decompose, and they'll be there until the earth is consumed by the sun because matter can't be created or destroyed. Then, when the sun eventually explodes like all other stars do, those molecules which still haven't been destroyed, because they can't, will go flying through space and eventually hit a planet that's in the stage of having life formed as earth once did, and your molecules will be used in that creation process, in a whole nother living being.
You've existed before. multiple times. You always have, and always will for all eternity.