Hi @Duong_Bui_Ngoc, are you running Open edX on a cloud server, or on your computer at home?
It must be running on a computer that has a static public IP address and no firewall on port 80. Once that’s the case, you need to buy the domain name you want (e.g.
myeducation.org) and then update the DNS settings with your domain name provider to point to the IP address of the computer where Open edX is running.
You may also wish to consider a hosted Open edX offer like we provide at Hosting | OpenCraft - you can use our control panel to set up an instance at the domain of your choice and try it free for 30 days; in that case, the provider will take care of all the technical details (HTTPS, backups, upgrades), and the only thing you have to do is update your domain name to point to it.