Is communism still in existence

Yes. Cuba remains a Communist country embodying many socialist ideals. Admittedly, it does not rise to the kind of Dictatorship of the proletariat that Marx envisioned, but it is the closest to it of any regime in history. However, most regimes, like China or Vietnam, that are still run by Communist Parties are effectively Leninist Capitalist states. No country that is not currently communist is considering changing to a communist system; it is effectively a moribund political philosophy.