Datang: the Starting System Makes Me Work Hard to Stay Alive

A madman who cared for his sister traveled to the Tang Dynasty, but took away the body of a frail and sickly man. What's even more tragic is that he turned out to be a cripple! Moreover, he has a beautiful sister. It is my greatest wish to have such a sister in this life. At this critical moment, he woke up the system. Human level, earth level, heaven level, immortal level, are you trying to push yourself up?