I never heard anything from evolutionist side that when you die what happens then. Could someone elaborate on this theory.
Your question implies a false dilemma. Acceptance of the theory of Evolution has absolutely no bearing on religious views concerning the afterlife - make people who agree that the evidence overwhelmingly supports the Theory of Evolution also believe in an afterlife. Many of them likely believe in the same afterlife you do. Others have other religious beliefs, and others have
no religious beliefs.
The Theory of Evolution is a model that explains the diversity of life. It has nothing whatsoever to do with anyone's belief concerning the existence or properties of an afterlife. Evolution speaks to what happens after we die as much as it speaks to the orbit of electrons in an atom: not at all.
The only reason evolution has an impasse with
some people on religious grounds is because it contradicts a literal reading of various religious creation myths, including the Judeo-Christian Genesis myth. But this false dilemma suggesting that those who accept evolution might not believe in an afterlife belies extreme ignorance on your part.