Repairablility is the most realistic path to immortality.
Your body gets damaged or old? You take your brain out and connect it to the latest disposable artificial body. Then proceed to throw your own old body in the trash just to flex.
Your brain starts crapping out from age or disease? You inject new neurons that gradually displace the old ones while forming connections with them.
This doesn't require any new magical tech to be discovered or supercomputers that exceed brains' processing power. Just development of existing tech and biology.