This is comprehensive and easy-to-follow step-by-step guide on how to configure OpenVPN on ubuntu via terminal. We also included a video to make the task easier for you.

1. Open the terminal. You may do it by using the following keyboard shortcut: Ctrl + Alt + T.
2. Install your OpenVPN client. To do so, type this command: sudo apt-get install openvpn-y
When asked for a password, provide the one you used when you created your OpenVPN account.
3. Go to the OpenVPN configuration directory using this command: cd /etc/openvpn.
4. Type in the command sudo wget nordvpn.com/api/file/zip to download the OpenVPN configuration files. If you get an error response that says the certificate of nordvpn.com is not trusted, you will need to install ca-certifictaes package using the command apt-get install ca-certificates.
5. If you do not have “unzip” package installed, type in the command sudo apt-get install unzip to download it.
6. Extract config.zip using the command sudo unzip zip.
7. To remove files that will no longer be necessary type in sudo rm zip.
8. Enter this command if you want to see the list of all available servers: ls -al. This will pull provide the full configuration file list.
9. Pick the server you want to connect to.
10. Fire up OpenVPN with the chosen configuration by typing in sudo openvpn [filen name] (Example: sudo openvpn at1.nordvpn.com.udp1194.ovpn).
11. OpenVPN will request for your credentials. Once it does, simply provide your NordVPN account details.
12. Finally! You are now connected to OpenVPN. To disconnect, open terminal then use the keyboard shortcut Ctrl + C.