I made an webserver with apach 2 on my raspberry pi 0. But they did not explain how to link your paid domain name to your webserver. Can someone tell me how to do that?
First, do you have a fixed ip adress in your home (or where ever you host the Pi) for this server?
If you do, then you talk to your ISP about putting your ip-name on their webservers. You also need to add the routing inside your home, but that's very router specific.
If you don't have a fixed address, you'll need to pay to join a DDNS (Dynamic Domain Name Service) company that follow your ip-address changes and make sure that your name and address are linked.
In either case, you'll need to set the hostname and domainname on the Pi so that everythig is consistent. You can do this through raspi-config which handles all the files. I know you need to modify /etc/hosts and /etc/hostname, but it's easier to do this with raspi-config.