It's safe to put some stock in the book of ENOCH because it's mentioned in the bible..
In Jude 1:14 we read, "And Enoch also, the seventh from Adam, prophesied of these, saying, Behold, the Lord cometh with ten thousands of his saints" (kjv)
The above is a quote from the book of ENOCH itself, not from some other place in the bible. If the bible is quoting the book of Enoch, then it's trustworthy. The above quote from the book of Enoch is found in Enoch I 1:9
"And behold! He cometh with ten thousands of His holy ones To execute judgment upon all, And to destroy all the ungodly: And to convict all flesh Of all the works of their ungodliness which they have ungodly committed, And of all the hard things which ungodly sinners have spoken against Him"
Fragments of the book of Enoch written in Aramaic were discovered in Qumran Cave 4, showing that it was among the other copies of scripture hidden away there.
There are tons of similarities as well.. the historical book of Enoch, which New Testament Jews had in their homes was well known & trusted in NT times.
Genesis 6:1-5
And it came to pass, when men began to multiply on the face of the earth, and daughters were born unto them, That the sons of God saw the daughters of men that they were fair; and they took them wives of all which they chose. And the LORD said, My spirit shall not always strive with man, for that he also is flesh: yet his days shall be an hundred and twenty years. There were giants in the earth in those days; and also after that, when the sons of God came in unto the daughters of men, and they bare children to them, the same became mighty men which were of old, men of renown. And God saw that the wickedness of man was great in the earth, and that every imagination of the thoughts of his heart was only evil continually.
Enoch I chapter 6-10:4
And it came to pass when the children of men had multiplied that in those days were born unto them beautiful and comely daughters. And the angels, the children of the heaven, saw and lusted after them, and said to one another: Come, let us choose us wives from among the children of men and beget us children. And Semjaza, who was their leader, said unto them: I fear ye will not indeed agree to do this deed, and I alone shall have to pay the penalty of a great sin. And they all answered him and said: Let us all swear an oath, and all bind ourselves by mutual imprecations not to abandon this plan but to do this thing. Then sware they all together and bound themselves by mutual imprecations upon it. And they were in all two hundred; who descended in the days of Jared on the summit of Mount Hermon, and they called it Mount Hermon, because they had sworn and bound themselves by mutual imprecations upon it. And these are the names of their leaders: Samlazaz, their leader, Araklba, Rameel, Kokablel, Tamlel, Ramlel, Danel, Ezeqeel, Baraqijal, Asael, Armaros, Batarel, Ananel, Zaq1el, Samsapeel, Satarel, Turel, Jomjael, Sariel. These are their chiefs of tens.
Enoch Chapter 7
And all the others together with them took unto themselves wives, and each chose for himself one, and they began to go in unto them and to defile themselves with them, and they taught them charms and enchantments, and the cutting of roots, and made them acquainted with plants. And they became pregnant, and they bare great giants, whose height was three thousand ells: Who consumed all the acquisitions of men. And when men could no longer sustain them, the giants turned against them and devoured mankind. And they began to sin against birds, and beasts, and reptiles, and fish, and to devour one anothers flesh, and drink the blood. Then the earth laid accusation against the lawless ones.