Grandson of the Ming Dynasty Emperor: I Really Want to Call the Police!

In an accident, Xiao Ran traveled through the Ming Dynasty. The good news was that he became the eldest grandson of Zhu Yuanzhang, and his status was extremely noble in the Ming Dynasty. The bad news was that he appeared in the fourteenth year of Hongwu and would not live long. The worse news is that Xiao Ran, who is a man in science and engineering, basically knows nothing about the history of the Ming Dynasty. Apart from knowing that Zhu Xiongying is the eldest grandson of Emperor Zhu Yuanzhang and the eldest son of Zhu Biao, he does not know anything else. Fortunately, the sky is the limit, and we have a mobile phone that can communicate in the 21st century: Xiao Ran: Hello, I want to call the police. I traveled to the Ming Dynasty. How can I come back? Security guard: Hello, it is illegal to file a false police report and you can be detained and fined.... Xiao Ran: Dear netizens, what would you do if you traveled to the Ming Dynasty and became Zhu Xiongying? Cheerful netizen: Wait to die! It's hopeless... Xiao Ran didn't want to give up. He thought he could still save something, so he called his good friend: Xiao Ran: Brother, how to purify fine salt... Xiao Ran: Can Queen Ma's illness be cured... Xiao Ran: How can I be a good emperor if I become Zhu Xiongying... Good buddy: First of all, you have to live past the age of eight, and secondly, you have to keep Zhu Biao, otherwise you have to face Emperor Yongle...