EDIT:
Are you talking about disposable template?
If not then read next:
Did you follow the readme correctly?
TemplateVM e.g. debian-12
AppVM (ProxyVM) e.g. sys-openvpn
You need to put them inside your AppVM and not in TemplateVM. And you need to rename or make a link from your myvmpconfig.conf to vpn-client.conf:
Copy the VPN config files from your service provider to the ProxyVM’s ‘/rw/config/vpn’ folder, then copy or link the desired config to ‘vpn-client.conf’:
You need to add this service to your AppVM and not to TemplateVM:
Next, add vpn-handler-openvpn to the ProxyVM’s Settings / Services tab by typing it into the top line and clicking the plus icon. Do not add other network services such as Network Manager.
You need to add killswitch. Like this but replace iptables rules with nftables:
You can also use Qubes OS firewall to restrict your VPN qube connections only to your VPN server IP:port: