Bonjour,
The various wikis and “how to” dealing with how to install NordVPN seem to me very complicated. 
I was able to install NordVPN very easily as a Firefox extension: two clicks and it’s done! 
Everything seems to be working perfectly.
Did I miss something?
note: Mac-Mini 7.1 + EOS Gnome
Cordialement
With the Firefox addon, only the traffic from your browser will go through the VPN server.
If you want to set up the VPN system-wide, then you would either need to use the CLI tool as described here: https://wiki.archlinux.org/title/NordVPN
or to set it up using your NetworkManager:
https://support.nordvpn.com/Connectivity/Linux/1061938702/How-to-connect-to-NordVPN-using-Linux-Network-Manager.htm
Please note that the command lines given in the link above are for Debian/Ubuntu (-based) systems. You need to use the equivalent of them for Archlinux.
Thank you for your reply,
I admit I don’t know how to install NordVPN with “Network Manager” on Gnome!
Apart from the NetworkManager which is already installed in your system, you would need the package networkmanager-openvpn which would enable you to import the .ovpn config files provided by your VPN provider and set up the VPN connection.
It is described in the link I posted in my previous post.
Thank you again,
I will try that this evening or tomorrow and let you know.
Cordialement,
Bon courage!