Since there is one carbon with 4 Fluorines attached to it, and both compounds are no metals, we use the covalent method for naming,
Here we ignore the prefix for the first element if it is 1. Mono. Then pay attention to the second one, it would be tetra, because tetra means 4. Here there are 4 fluorines.
Because group 2 is very reactive and forms salts with other non metals. Example Calcium Chloride. Calcium is from group 2, forms ionic salts with other non metal, and exists as solid at standard temp and pressure.