When naming compounds, the use of prefixes depend on the type of bond made. In this case, calcium and bromine form a ionic bond because calcium is a metal and bromine is a non-metal.
Ionic bonds are not named using prefixes. So no matter how many atoms there are, you will simply write the name of the element for the first element.
For the second element, you name it as well, but only use the root name and end it with -ide.
