Allow connections from a domain/port around the network lock and vpn?

[wandigo 1]

I am not technical. I am wondering if there is a way to allow some connections from outside the network lock and vpn?

For example, I may connect with Windows Remote Desktop/Plex from my cell phone.

I set a domain up pointing to a dynamic dns updater. This sometimes allows me to conveniently access the address and port... but this method does not always work, or does not always work well.

I don't completely understand if the 'Routes' or 'Network Lock > Addresses Allowed' panels are what I should be using.

Is there a way to allow connections coming from a specific domain and port? Or do I need the specific IP addresses?

OR, is there a way to allow specific port connections around the network lock and vpn? If that is possible, may I be able to use my home IP address to connect Windows Remote Desktop in (while still maintaining the network lock and vpn benefits to other connections)? Although, I was under the impression that this second idea was not so good as stated https://airvpn.org/faq/port_forwarding/.