What's the difference between using nouns as attributives and adjectives as attributives? For example: does Canada boy have the same meaning as Canadian boy?

What's the difference between using nouns as attributives and adjectives as attributives? For example: does Canada boy have the same meaning as Canadian boy?

No difference, idioms, by reading more dead, sometimes can be universal
as you exampled,"canadian boy" is right,while "canada boy" is wrong.