Everyone Reincarnates, and I Can Simulate Lives

This is a world where everyone can reincarnate. Once people turn eighteen, they get one chance to reincarnate into another world. All the power they gain through reincarnation is bestowed upon their real selves. They can also bring back most of what they acquire in the reincarnated world. He Song arrives in this world with a Life Simulation System, outpacing everyone from the start and climbing step by step toward the highest peak.