The opposite of the ancient Egyptian afterlife, which emphasized immortality and a journey to the Field of Reeds, could be considered the concept of oblivion or non-existence after death. In this view, death leads to a complete cessation of existence, with no continuation of the soul or consciousness. This contrasts sharply with the Egyptian belief in a judgment that determined one's fate in an eternal afterlife.
The afterlife was a main concern of the Egyptian civilization.
The tombs of the ancient Egyptian pharaohs and nobility are filled with items that would be needed in the Egyptian afterlife. Also the uncovered writings of the ancient Egyptians speak about the afterlife.
The ancient Egyptian belived in afterlife. And that was why the mummified the dead in preparation for this.
The afterlife
They did not do anything. It was part of their belief.
Heaven.
Mummification
The book of the dead.
=== === === === === ===for more information about why the heart was left in the body type in this question What were the steps of Egyptian afterlife?
Pharohs and their belongings to help them trough the afterlife
Embalming
the answer is 50 to 100 thousand years