In The Lord of the Rings, if Orcs as mentioned by J.R.R. Tolkien were the Elves tortured by Melkor to serve his will, does this mean they also were immortal?

Thank you Guilherme for the A2A!This is a difficult, perhaps impossible question to answer.  Tolkien certainly never provided a definitive answer in his canonical works.  On this subject even his personal letters reveal an unusual level of diffidence and irresolution.