Wireguard

setup:

https://github.com/angristan/wireguard-install

connect (if GUI failed, using GNOME, KDE supports wireguard via GUI):

nmcli connection import type wireguard file wg0.conf

off:

nmcli connection down wg0

on:

nmcli connection up wg0

OpenVPN

Autostart OpenVPN

https://askubuntu.com/questions/1037723/openvpn-autostart-ubuntu-18-04

If you save your configuration as a MY_CONNECTION.conf file in your /etc/openvpn directory, you can do the following:

systemctl enable openvpn@MY_CONNECTION
systemctl start openvpn@MY_CONNECTION

where MY_CONNECTION is the same from MY_CONNECTION.conf.

So if you have multiple connections, you would have multiple systemctl calls.

systemctl enable openvpn@MY_CONNECTION1
systemctl start openvpn@MY_CONNECTION1
systemctl enable openvpn@MY_CONNECTION2
systemctl start openvpn@MY_CONNECTION2

etc.