Whether you use a credit card or anything else, the process of buying things on Taobao is as follows:

You select the product→take a photo→confirm the order→pay→the money enters Alipay ( In other words, Alipay is a third party relative to you and the seller, and the money is placed with the third party at this time) → the seller delivers the goods → you check that there is no problem after receiving the goods → confirm the receipt (confirming the receipt means that the transaction It’s done, you have received the goods, and the money that just entered Alipay has also entered the seller’s Alipay. At this time, the money is no longer yours)

This is roughly the process.

--------

As for you, what you mentioned above is an overdraft card. Isn’t it necessary to open online banking for an overdraft card? I don't understand a bit. This has nothing to do with it. In fact, if you pay successfully, it means you have gone through your bank's online banking. Credit card payments are generally easier than ordinary debit cards, but the limit is generally lower.