Router have 2 ip address private ip and public ip (PPPoE). How to point domain to setup a homeserver

I bought a domain from Hostinger. Eg:homelab-server.site I check my router having 2 ip address: public ip: A (showing in browser) private ip: B (showing in router from PPPoe section) I try to open some port from my computer. I can access my website only from B ip address. Eg: B:80, B:3000 Now I want to point my domain from Hostinger to my ip to check my webserver. But pointing to both A and B are not working. Anyone can help me to config in my case?

Question by Thang Nguyen on Super User, licensed CC BY-SA. We show a short excerpt and link to the original thread as credit.