Most of this boils down to how the routing tables for the "client" PC is set-up.
It is easy to add static routes for static destinations that use a specific interface/route.
But having two applications that connect to seemingly random destinations (e.g. a Web-browser and a BitTorrent client.), and let each use a different interface sounds difficult.
I have read that there are (software) firewalls that can be used to mangle packets from certain applications and redirect them to a specific interface.
Is it posible to do something like this having 2 diffrent networks?
Like connecting PC to PC via LAN with like 192.168.1.1 and .2 and still be connected to internet via 10.10.10.1 ?
When I did it when it type www adress it was looking for it at 192., but when i disconnected 192, it was all fine. Like it wouldn't use all avaible interfaces... how to set the default one ?! Is it even posible to config browser to use 10.10.10.1 gate and not the one that is in interface 1 ?
This should be possible if you make that 10.10.10.1 router the default gateway.
And leave a route for 192.x.x.x destinations on the other interface.
Assuming you are using Windows, the "route" and/or "netsh" command can manipulate the routing tables.