are all the electrons on the outer-shell donated in metallic bonding

At any one time, most of the electrons in the outer shell are donated, but what happens is that when the electrons get enough energy to escape, they end up being absorbed afterwards by a different cation and then being donated again and this continues forever, however generally at one one time most of the electrons are free.

are all the electrons on the highest energy level donated in metallic bonding.
e.g. titanium has two electrons in 3d sub-shell, so does it lose those 2 electrons?

or is it that 1 electron is removed from the outer-shell

could you also give an explanation please