What happens if my player character is resurrected(?) by a Necromancer? [closed]

My player character was killed off by the DM, my party found pieces of my body in a room.

They’ve taken my head back to the Necromancer we met.

My questions are:

What can a Necromancer do? Is it just resurrection or can they do revive? Or something else?

If I’m resurrected, doesn’t this make me undead? And if so, doesn’t that mean I wouldn’t have a need for Hit Points?

Do resurrected characters automatically re-attune to their magic items?

In the basic rules (Pg. 58) as well as in the DMG (Pg. 138), the section on attunement states (emphasis mine):

A creature’s attunement to an item ends if the creature no longer satisfies the prerequisites for attunement, if the item has been more than 100 feet away for at least 24 hours, if the creature dies, or if another creature attunes to the item.

By this logic, if a player character dies, then their attunement to any magic items would end. If that character is resurrected, for example with the Revivify or Raise Dead spells, will their attunement be restored along with their life?

Can a creature that has been Reincarnated be Resurrected using the old body?

Say a creature (humanoid) was killed and then reincarnated through the Reincarnate spell, gaining a new body. (Note that Reincarnate does not destroy the old body). Then that creature is killed again.

Can that creature be brought back to life through a Resurrection spell using the creature’s old body? And would it resurrect in the old body or the body from Reincarnate?