Requirements 1: Shanghai departure certificate. Also known as the commitment letter to leave Shanghai. If you want to leave Shanghai for home in the near future, you must issue this certificate. You can't go home without it. The distributing unit is the community neighborhood Committee (village Committee) where Shanghai is located, and the receiving unit is the community neighborhood Committee (village Committee) you need to go to and the checkpoint on Shanghai Road that may be needed.
Requirements for returning to Shanghai: acceptance certificate.
Report your planned trip in advance and learn about the isolation hotel/health station, etc. Remember to inform the neighborhood committees and community neighborhood committees, otherwise there will be few units calling to verify the situation every day and not many different people.