I don't mind explaining.
As soon as Adam ate, both of them died spiritually.
Man is body, soul (mind) and spirit.
God then pronounced the curse, part of which was "from dust you were made to dust you will return" and he also said this is "because you listened to your wife and disobeyed"
It wasn't happening before that. We get old and die and the body returns to dust because of Adam's sin.
The Christian faith, while alive on earth is only about the spiritual side, the spirit coming to life. The body coming back to life happens later at the return of Christ.
1 Corinthians 15:52
In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed.
Then those who alive at the time of the second coming
Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air:
This is the bodily change from a body that dies to a body that is immortal.
Later everyone else is raised and there is the white throne judgment.
12 And I saw the dead, great and small, standing before the throne, and books were opened. Another book was opened, which is the book of life. The dead were judged according to what they had done as recorded in the books. 13 The sea gave up the dead that were in it, and death and Hades gave up the dead that were in them, and each person was judged according to what they had done. 14 Then death and Hades were thrown into the lake of fire. The lake of fire is the second death.
The second death is the obliteration of body, soul and spirit in the lake of fire and that doesn't take place until a thousand years after the return of Christ.