Our school district phone system is a Cisco phone system, and we deploy two different phone types in the school district.
THIS LINK will take you to the document that we have describing the use of the Cisco 7821/7841 phones. These phones are the base model of phones in use in the school district, with a monotone display screen.
THIS LINK will take you to the document that we have describing the use of the Cisco 8941 phones. These phones are the video phones in use in the school district, with a color display screen.
Your phone should display your name, or the name of your location, on its display. If it does not, create a help desk ticket to get this issue fixed.
Your phone should, in most cases, be set up so that you have a voicemail box tailored to your identity. Access that voicemail by following the instructions for your model of phone. The default voicemail password is "12345" (without the quotes).