You're right. It's not just a book. It's the Church Christ created when he told Pope Peter: "And I say to thee: That thou art Peter; and upon this rock I will build my church". This Church is the "one, holy, catholic and apostolic Church" (325AD). This very Church canonized the Bible we know today around 400AD
Its not some random book, it is the verified writings by the institution the Living God created by himself for his disciples to carry on.
You've been fed distillations of the truth so removed from its breadth that it seems trivial. It's not. It goes way deeper than you realize. When exploring more you will have to come to the realization that you're going against thousands of years of human history, logic, and spiritual understanding. This historically short blip of material "enlightenment" is not it.