how is it possible that when you look at the night shy you may be looking at stars from millions of years ago

this is beacuse stars are always in the sky

Explanation:

stars are always in the sky they are in the sky we just cant see it through our naked eye ... Also, while those super-massive stars will die suddenly as supernovae, most stars experience much slower deaths taking hundreds of thousands or millions of years to play out. Examples of famous stars already in the act of dying include Arcturus and Aldebaran.