How to make a web server on ajenti with external access?

Question

Ajenti

For example in Windows.
I bought a domain - make a record on the server A from the ip of the machine on which the server is located.
In open server, I made a domain, made an alias, and that's it - your local server has access from the Internet.
I absolutely do not understand how to do this in ajenti, or rather, I only managed to get to the test domain from LAN once.
It costs ubuntu server on a single board (Orange Pi)