I have a China Mobile SIM card inserted into my iPad 3. Please tell me how to make calls, send text messages, check costs, and check data traffic. Thank you all. Urgent.

ipad3 does not have communication functions.

To check the phone bill, you can check it on the official website

When there is wifi, you can make free calls through facetime and send free text messages through iMessage, but both parties must have iPhones or iPads at the same time. Connect to the Internet.