[Spoilers] Why does Sasuke think he can be immortal with his doujutsu?

[Almighty Ra]

He doesn't mean literally but figuratively like Indra is immortal due to his will. Sasuke is trying to reach that level of immortality

 

[MAN OF SIN]

in the *********** version, sasuke mentions the line of succession while talking about immortality. He might be trying something similiar to ashura/indra so he can have his chakra reborn through the ages or something

He doesn't mean literally but figuratively like Indra is immortal due to his will. Sasuke is trying to reach that level of immortality

There are enough differences between Sasuke and Madara to know that he might not be reincarnated into Sasuke 2.0.