How many valence electrons does he have?

The number of valence electrons of helium is 2 because of its configuration which is $1s^2$ Hovewer, the valency is 0 because it is already stable and none of the outermost electrons are involved in the formation of chemical bonds. read more

Helium has 8 valence electrons. It is a noble gas. none = 0. read more

Valence electrons are the electrons located in an atom's outermost shell. In helium's case, both its electrons will be valence electrons. Its electron configuration can be used to better show this "He" = 1s^(2) Two electrons in its outermost (and only) shell, two valence electrons. read more