How to forward one local PC through VPN ?

Hi, i have configured PPTP client interface, it connects, and appears reachable route. Now i need to forward one IP address from local net through this route, to another country, how to do that ? I have idea only about mangle…

Create a mangle rule, when packet is from your host ip, then action: set routing mark. Set the mark as PPTP

Now add a route, when dst-address is 0.0.0.0/0 AND routing mark=PPTP, then route it through your PPTP interface.