Uploading your consciousness to a machine wouldn’t really extend your lifespan. Think of it like moving a file from one device to another; the file isn’t actually moved, you just get a copy on the second device. You and your digital clone will also begin to diverge immediately as the lived experience of being a new digital entity would be different from continuing life as a meat person.

The closest you can get is to Ship of Theseus it; get a machine implant which gradually takes over brain functions as cells die or parts of the brain fail. Single stream of consciousness in a single body, now fully digitised. Incidentally this is also closer to biological processes to replace cells, though the brain cells renew much less frequently then other cell types. I think some areas don’t naturally get replaced over a lifetime too but I’m not certain on that, either way you’d want to go faster than natural cell replacement.

Alternatively you could make the transfer process dissolve your meat brain. Personally I’d say you are dead and your clone lives on but its the same argument as Star Trek style transporters; the clone still feels like it’s you so if they got to where you want to go does it really matter?