Help routing 2 layer 2 networks

[makitos666]

I have 2 virtual networks in a layer 2 VPN using OpenVPN.

I have my plain network 10.11.12.0/24 and my other plain network 10.12.13.0/24. All machines on each network, as it is layer 2, have totall visibility.
I want to interconnect these 2 nets with restricted visibility, so I deployed a PFsense with 3 interfaces. First interface is WAN, to provide Internet to PFsense and for me to manage them. The other two interfaces al tap0 and tap1 created by OpenVPN.

I know I must mount a static route between two nets, but first is seems thjat I need a valid Gateway in every network, and I don't have any.

For now, I have visibility between virtual net1 and tap0, and between virtual net2 and tap1. But I think that without a gateway I will not have visibility between net1 and net2.

This is where I am stuck, any advice?

Thanks!