The book of Enoch was apparently included in the Bible canon for 500 years, then removed by the Council of Laodicea in 364 AD. Because it confirms the Genesis 6:2-4 account, and answers/aligns with 2 Pet 2:4 and Jude 1:6 I have referenced it in regard to fallen angels, and pre- and post-flood giants.
The biggest criticism of the Book of Enoch is that "Enoch didn't write it", but if it aligns with scripture, I consider it. The gospels of Mark and Luke weren't written by Apostles; neither of them are listed in the 12. The Bible also refers to the Book of Jasher in Joshua 10:13 and 2 Sam 1:18 (which is a book of Songs, according to my research), yet it, too was removed from Bible canon.
I have one hub that shows the alignment of the Book of Enoch with the Bible called "The Origin of the Nephilim". My rule of thumb is this ~ be grounded in the Bible before branching out into any other extra-biblical material; always test what you read to make sure it aligns with the Bible and keep your faith in the Bible, only "observing" what is in extra-Biblical material. Blessings!