Roadwarrior connects to Site A but I want to pass on to Site B via S2S VPN

[samnet]

Can someone detail the steps needed to make Rd Warrior vpn pass to site B via Site A.
I have tried several trick but cant find a successful way to do it.
the reason being is that Site B has no inbound traffic due to restriction from a Jackass ISP who cant manage their own security infrastructure. While Site A has inbound.
so what I ended up is making Site B ovpn client and Site A is the Server and works fine.
I just want to do Rd Warrior to Site A to goto site B.

[Patrick M. Hausen]

The road warrior network needs to be a part of the "remote networks" as viewed from site B.

[samnet]

The road warrior network needs to be a part of the "remote networks" as viewed from site B.

Thanks
can you explain more, do i need to goto to client side config on Site B and define remote subnet? keep in mind that road warrior subnet is not fixed to a subnet it varies