Online banking should bring ID card and ABC card to the bank counter. When you arrive at the bank, you tell him to apply for online banking, and he will give you a form to fill out, and then you can apply. He will ask if you want to use KBao or dynamic password card. KBao is charged, but it is safe and convenient. It can also be used in internet cafes, without worrying about losing the reinstallation system certificate. These two codes are given to you by the bank staff when handling. These two codes are used to download the security certificate. You must have a certificate when trading, otherwise you cannot trade. As for the digital signature you mentioned, it should be a certificate, a digital certificate. After the transaction is completed, you can transfer money and spend money online.