What is the element's name and symbol? is it a metal, nonmetal, or metalloid? which family does it belong to? how many protons, neutrons, and electrons does its neutral atom have?

Krypton is non metal it is part of the noble gas family.  It has 36 protons and 48 neutrons. Its symbol is Kr. Krypton, like the other noble gases, is used in lighting and photography. Krypton was discovered in Britain in 1898 by Sir William Ramsay, a Scottish chemist, and Morris Travers, an English chemist, in residue left from evaporating nearly all components of liquid air. Neon was discovered by a similar procedure by the same workers just a few weeks later.

Compound light microscope