This is a Dell Optiplex 3240 AIO Series, and it is issued by my school since 2016. It is similar to iMac, except, it is all black, has a Dell logo instead of Apple, have the power light on the bottom right corner of the front of that computer (iMac does not have one), in different appearence, has some buttons and disc reader on the right side (iMac only has one button (power) on the back, and I believe it does not have a disc reader), and auxiliary ports on the left side (I think iMac has auxiliary ports on the back). Also, its main peripherals are not wireless, unlike iMac. Since this computer is school issued, it would not let me validate isOnline and run programs I installed.
C2A!