In this kind of situation, it may be impossible for us to help you just quite yet. There are hundreds of ways a business network can be set up, and a hundred more ways they could be allowing remote access. The best thing to do at this point is to get with your technology person (MIS Manager, IT Manager, CTO, etc.) and explain what you want to do. They will most definitely be able to point you in the right direction. Once we get the information about your network and how it's set up, we can troubleshoot with you until we get it working for you.
One thing may be to ask a co-worker how they're doing it. Perhaps they're using a "VPN connection," which would allow you to access your work network from home. Or, perhaps they have individual "port forwarding" set up for each machine for VNC access.
At this point in time, though, I think your best source of information is from the tech person at work (or whomever manages your network and computers). Otherwise, we'd simply be grasping at straws here, since we know nothing of the network setup.
