You can bring your passports (with a valid entry stamp) or Foreign Permanent Resident ID Cards to the service offices of telecom operators such as China Telecom, China Mobile, China Unicom, and China Broadnet, to apply for a SIM card and activate mobile communication services in China.
Mobile communication service plans typically include a combination of call minutes and data. Different operators will provide a range of plans to suit different needs, so you can choose the one that best suits you.
Note: The plans often offer a limited amount of mobile data. Consider disabling internet access when not in use if the data allowance is small. Or, you are advised to consult the telecom operator for an appropriate data plan if you need to use a large amount of data.