This is a binary compound of an halogen and a metal.
Copper may have two oxidation states, +1 and +2.
Then you first have fo state the oxidation state of the copper in this binary compound.
The iodine is the halogen. It is in the form of Iodide ion, whose oxyidation state is -1.
Then you conclude that copper here has oxidation state +1.
Then the systematic name is: Copper(II) iodide
