No need to register in advance. The health code relies on the real-name authentication system and implements one person and one code. You can apply on platforms such as Alipay and WeChat. You don't need to register for the first time, but you need to log in with real-name authentication (you need to declare your health for the first time) to obtain and show your health pass code. If you are prompted that your health code has expired or expired, you need to apply for a new claim.