Not quite, but some folks believe that when you die you turn into one. NO idea how true that is.

But the spirits are just beings that are made of up mana and basically provide the energy the world needs to sustain itself. Like I said before, without them, the world would die.

I don't know if I would call them "living beings" like human and animals, but they are alive in a sense and have their own forms. They also don't really make themselves visible to humans.