You are free to believe anything you wish; that angels dance on the heads of pins, that dead people come back to life, that snakes talk, whatever. Just don't confuse "belief" with an extent reality where supernaturalism doesn't exist.
Why would I be wiser to believe that the planet is 6 000 years old, that humans lived to be 900 years old, etc.?
While you attach an entire worldview to what is written in a book you attached "holy" to a book is simply that, a book. Until there is a way to connect a supernatural being with the authorship of a book, it's safe to assume that the book is, in fact, merely written by men. That is precisely what we have with the.Bible. A book written during a superstitious age when people did believe falling off the edge of the planet was a literal danger. Believe in magical gardens, a flood that never happened, angry gods that wipe humanity from the planet, whatever you wish but don't presume that I am under any obligation to cower in fear and superstition before any human invention of god.