Part of 1 Enoch describes?

Answer 1

That depends on how you interpret it.

Nephilim, fallen angels, Watchers, aliens....who knows?

Answer 2

Part describes the names and functions of the angels, both good and evil ones. It also names the ring-leader of the angels of the rebellion. It names Gabriel as the leader of the troop of angels that fight against the minions of the evil ones.
Part describes the treasuries of water and wind and hail and snow...etc., reserved for use in the Day of Judgement.
Part describes the fixed courses of the sun, moon, stars, and planets, to be run at their appointed times, and the gates through which they enter and depart.
Part describes the judgment of God upon all of the ungodly and the lawless.
Part is the prophesy of the goats and cows, and the Dabela who oppresses them.
Part is the eventual outcome and triumph of good over evil, and the forgiving of the unfortunate victims, along with the vindication of the Saints

Answer 3

Jude 1:14 And Enoch also, the seventh from Adam, prophesied of these, saying, Behold, the Lord cometh with ten thousands of his saints, 15 To execute judgment upon all, and to convince all that are ungodly among them of all their ungodly deeds which they have ungodly committed, and of all their hard speeches which ungodly sinners have spoken against him.