Was the Bible the first religious book ever created?

Answer 1

Number one - The Bible is not a religious book. Religious is a practice or an act not a thing. Doctrine is that thing which one can religiously adhere to and practice. What is now referred to as "The Bible" contains some of the oldest writings known to man. Initially those writings would have occurred on animal skins which were kept rolled up (scrolls). Later scribes of the Church would copy the scrolls and the letters of the apostles onto a book which you now refer to as "the bible"

There were and still are, other doctrines however I am not aware of a documented doctrine which predates any of the biblical texts.

Answer 2

To date the oldest known religious text is the Kesh Temple Hymn of Ancient Sumer dated as being written around 2600 BCE. This is about 2000 years before the writing of any of the Biblical tests or their components.