Read Narnia. Probably in the order they were written.
The Lion, the Witch and the Wardrobe
Prince Caspian: The Return to Narnia
The Voyage of the Dawn Treader
The Silver Chair
The Magician's Nephew
The Last Battle
The Horse and His Boy (Read this whenever. Don't skip it though, it's good. I recommend saving it to read after the Last Battle.)
As for Tolkien I'm not sure. I've read LotR, the Hobbit (<One of the best books ever booked), and the Silmarillion. The Silmarillion gives you tons of info about the beginning of the Middle Earth universe, Morgoth, Sauron's beginnings, the early history of Middle Earth, and stuff like that. Some people think it's really boring. Tolkien didn't even want it published, he just had it for his own reference. But it definitely has good parts.
Igh. I'd say read the Silmarillion after LotR. Never read those other Tolkien books.
EDIT: My bro says to read the Children of Hurin before the Silmarillion. Because the Silmarillion has a much shorter version of the Children of Hurin in it.
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