If you are referring to Very Small Aperture Terminal (VSAT), then you would work with that provider. Obtain a static Public IP at both sites. Use a router that will allow VPN creation.
If in fact you are talking about Very Small Aperture Terminal (VSAT),then you really need to understand VSAT’s limitations and ensure that this technology will work for your intended use.
Usually VSAT service provider will provide a point to point link between two sites you want, its like a lease line but uses a Satellite to provide the point to point link. Normally the service provider will run a co axial cable from the satellite dish to your equipment room and they will provide a modem whihc can be connected to your router using a serial cable (typically V35). As far as IP address are concerned its depends on your design