WAN + VPN + browsing

Hello
I have router board connected with internet all the bridges have internet from the wan port
now i would like to install VPN client in the same router my question is :
How i can make isolate to specify that this site go throw VPN and other browsing go out of VPN ?
and how i can specify this bridge goes VPN and other out of VPN?

thank you in advance

in other meaning
how i can let facebook.com goes from WAN1 and other sites goes from WAN2

UP UP UP