Paul McCartney is not dead. As of mid-2022, he was still touring, in fact, and he probably still would be if the coronavirus pandemic hadn't canceled his gigs. He gives interviews, he has a website, he occasionally appears in the tabloids.
Pretty good for a guy that some conspiracy theorists think died in 1966.
The "Paul is dead" conspiracy goes something like this: On Nov. 9, 1966, Paul McCartney got into an argument with the other Beatles, stormed out of the studio and was promptly decapitated in a car accident. To cover the whole thing up, the band hired a look-alike (and sound-alike).
After going through all this trouble, though, the band then took great pains to drop clues in their album covers and lyrics to hint to the public that something was amiss. For example, on the cover of the Abbey Road album, all four Beatles are photographed striding across a zebra crossing, but only McCartney is barefoot and out of step with the other three. This must mean something, right? Despite public denials by the band (and many, many public appearances by McCartney), fans couldn't just let it be, and came together to look for more clues.