Is Narnia about God

Yes, think about it. In The Lion, The Witch, And The Wardrobe Aslan dies for Edmund (Jesus died for our sins) and Aslan later rises from the dead. Like Christ's resurrection.

In another one of the books, Aslan turns into a lamb. Jesus is known as the Lamb and Lion.

If you're asking this because you are a Christian and want to know if it is good, I'd recommend it to anybody.