The supplementary card can only be applied for if you have the card. You can ask your parents to help you apply for it

The supplementary card is relative to the main card. Each main cardholder who opens a credit card can apply for an additional card for other natural persons with full capacity for civil conduct, or natural persons with limited capacity for civil conduct who are over 13 years old (applicants for supplementary cards who are under 18 years old must obtain the consent of its legal representative). Each main credit card can apply for up to two supplementary cards, and the main cardholder has the right to request cancellation of its supplementary cards. The credit limit of the supplementary card is designated by the principal cardholder on the premise that it does not exceed the credit limit of the corresponding principal card; if the principal cardholder does not specify it, the credit limit of the supplementary card is the same as that of the principal card. All transaction amounts and corresponding interest and fees of the supplementary card will be charged to the main card account, and the main cardholder shall bear all repayment responsibilities. However, the principal cardholder and the supplementary cardholder are jointly and severally liable to each other for repaying the amounts owed. Supplementary cards can bring a lot of convenience to our daily card swiping applications. If your child goes to school in other places, you can apply for a supplementary card for him or her at the same time as you apply for the main card. This is not only convenient for your child to use the card, but the limit can also be controlled by you. It is a good family finance. Product selection.