My husband applied for immigration to Canada for me, and my visa came down. Now he wants me to get a maple leaf card, but I'm still in China. Why?

To apply for a maple leaf card, you must be present in person. No one can do it for you. So you have to go to Canada. During the validity of your immigrant visa, you can enter Canada with an immigrant visa (which is valid once), get off the plane at the airport (Vancouver International Airport or Toronto International Airport), and apply for a maple leaf card in the office hall of the airport immigration office. You will be asked to leave your address in Canada when you apply for a card, and it will be mailed to you after the card is completed.