Minors can send a courier through a courier company, but they need to fill in the guardian information on the courier form. Usually, the courier company will provide you with packaging services, or you can package the goods yourself and send them to the courier company or post office. In the process of sending express delivery, whether the contents and packaging of the items sent are in good condition is a confidentiality principle that express delivery companies must abide by. The staff will not open or inquire the contents of the email at will to protect the privacy of the sender. You also need to pack your own items to use the express cabinet. Express cabinets only provide warehousing and transshipment services, not packaging services.
In short, the rules of the courier company are different. Please consult the local courier service provider for specific requirements, so as to answer your questions more accurately.