A storage device includes a memory device including a first memory region, a second memory region, and a third memory region, the first memory region having a lowest bit-density relative to the second memory region and the third memory region, a second memory region having a medium bit-density relative to the first memory region and the third memory region, and a third memory region having a highest bit-density relative to the first memory region and the second memory region; and a controller configured to control the memory device The controller is configured to distribute data received from a host to the first to third memory regions based on attributes of the data, to determine a current state based on a data distribution amount for each of the first to third memory regions and a respective size of each of the first to third memory regions, and to perform an action of increasing or decreasing a size of the second memory region under the current state based on a reinforcement learning result for mitigating a reduction in lifespan of the third memory region.