I'm Using Kali Linux i want to use VPN connection but in the network option it wasn't there
so i installed opnvpn using apt-get intsall command and al its dependencies.
for configuration i downloaded .ovpn files from vpnbooks.com
and tried:

openvpn --confiq vpnbook-de233-tcp433.ovpn

it gaves an error saying config couldn't open .

so how do i configure .ovpn file and
how do i add username,password,gateway,and certificates to the VPN and configure it?

i know its a tough one but i hope somebody will help...