You can start your call center and switchboard configuration by making basic settings such as default area code, key assignments on your softphone. To set up your basic settings, go to Settings > Call Center Settings and select the Basic Settings submenu.
On this screen, you can set the codes for quick actions you can take on your hardware softphone software and make some other basic settings. While making these settings, you can hover on the question mark icons to check the relevant info.
Note that, usually, you don't need to change these default settings.
After the basic settings, you can continue your call center configuration by connecting your SIP (or analog) lines, that is, your phone numbers, to Infoset.