Immortality is already technically possible by plugin ones head onto new healthy body every 100 years or so.
You can google "Sergio Canavero" or "Valery Spiridonov" for more technical details.
Whether it will become popular or widespread in the future remains an open question due to various moral and cultural implications.
No it's not. Your head is what matters, not the body. Your brain will age no matter how many body switches you make and eventually your brain will die. That's not even close to immortality. The biggest advantage to that is that any disease in your body that doesn't affect your head can be ''treated'' by switching your body. Still very early on that technology tho.
Sure. But it is pretty close to it.
Also considering it adds double digit number of centuries to your lifetime you are more than likely to witness future scientific breakthrough`s and make it "a real thing" later on.