The reasons Enoch did not die is explained in the New Testament. “By faith Enoch was taken away so that he did not see death, ‘and was not found, because God had taken him’ for before he was taken he had this testimony, that he pleased God.” (Hebrews 11:5)
Genesis 5 records a fact about Enoch we should not miss. The text says Enoch was 65 years old when his son, Methuselah, was born (Genesis 5:21). The next verse says that it was not until after Methuselah was born that he started walking with God (Genesis 5:22). In other words, Enoch only walked with God for 300 of his 365 years. Enoch should have died in his sin, but was rewarded with life. And he was not the only one to cheat death . . .
“But without faith it is impossible to please Him, for he who comes to God must believe that He is, and that He is a rewarder of those who diligently seek Him.” (Hebrews 11:6)
“ He will swallow up death forever, And the Lord GOD will wipe away tears from all faces; The rebuke of His people He will take away from all the earth; For the LORD has spoken. And it will be said in that day: "Behold, this [is] our God; we have waited for Him, and He will save us. This [is] the LORD; we have waited for Him; we will be glad and rejoice in His salvation." (Isaiah 25:8-9)