is this the 1st or the 6th book? unclear

i never realized how much of a religious metaphor narnia is. this is my first time rereading them since i was a child and i completely missed all the religious allusions.
this entire book is essentially a retelling of the creationism story. the kids ends up in narnia and witness the birth of narnia, aslan js god and creates the grass trees and animals through song and then pairs the animals off and gives them voices. some animals are given speech and some aren’t but he tells them to treat everyone equally. the kids are then given an adventure which honestly only happens in the last 10 pages-most of this book is boring setup in england. the adventure is for them to go find the a tree and take an apple but not eat it, a metaphor for the garden of eden. the garden is beautiful and the apples smell delicious and an inscription describes how the apple will give them everything but they don’t eat it and instead return it to aslan. meanwhile the witch from another world eats the apple and is the evil in the world that needs to be eradicated while the kid’s uncle represents greed and sin.

i started reading this after watching/reading The Magicians which is heavily based off of narnia.

i think it’s interesting that this story is mostly unrelated to the other narnia books and is a prequel but how both books have an edmund character who is an overlooked boy constantly tempted by evil and needs to find it in himself to choose good who is accompanied by a girl relative..

also weird that the outsider human children are treated like kings and queens in this new world