One day

Gen 2:17; " But of the tree of the knowledge of good and evil, you shall not eat of it: for in the day that you eat thereof, you shall surely die."

Gen 5:5 "And all the days that Adam lived were nine hundred and thirty years: and he died."

II Peter 3:8 "....that one day is with the Lord as a thousand years, and a thousand years as one day."

So we see, Adam did die the same day he ate of the forbidden fruit, because he only lived 930 years, he didn't live past 1000 years which equals 1 day.