In order to access your office computer remotely, you'll need to know either it's network name, or it's IP address. The steps below help you find the address your Mac has at the moment. Click on images to enlarge them.
1. Click on the 'Apple' menu in the upper left-hand corner of the screen, and select 'System Preferences'
2. In the System Preferences window, click on the 'Network' pane.
3. In the Network pane, with 'Ethernet' selected in the list on the left, read your IP address from the top listing.
Note: IP addresses on Wi-Fi networks change quickly. If your system is not connected via an Ethernet cable, you may have trouble accessing it remotely.