Configuring your VPN with cmst (Connman System Tray) in a pristine Debian Buster and LXQt is almost straightforward but not quite.
How to reuse OwnCloud/NextCloud credentials in other sites.
How to prevent your DNS leaks when connecting through openvpn under Ubuntu (artful)
How I turned a Raspberry Pi 3 into an Airplay audio player
How I turned a Raspberry Pi 3 into a Spotify player