Typically a baby will learn to crawl between 6 to 12 months. Every baby develops differently.
If he is not "motivated" by his toys, you can also try to encourage him by being his "model". Try being on all fours when playing with him. Babies often learn by mirroring the people around them. Seeing you crawl around may pique his interest and start modeling after you when he is ready.
Hope this helps.
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