What's the procedure, urgency, online, etc. Because I dropped out of school in Australia

First of all, if you are a student visa, you can tell the school why you have been suspended and give proof. You can contact the school directly without contacting the immigration office, but your semester must be within the validity period of your visa.

You have to remember that you must get permission from the school before you can drop out of school and return to China, otherwise, you may become an illegal resident in Australia. It is also possible that he will never come.

Watch out! Good luck!