there is no such Pokemon
No, you cannot find cyndaquil in LeafGreen.
LeafGreen version does not have Growlithe.
There aren't growlithe in LeafGreen. FireRed has growlithe, LeafGreen has vulpix.
That item doesn't exist in leafgreen.
you cant go underwater in leafgreen!!
Piplup does not exist in Pokemon LeafGreen or FireRed.
Psyduck is in firered not leafgreen you can find it using a good or super rod in the safari zone.
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you cant
Nowhere.
you find chinchou under the sea when you diveChinchou cannot be obtained in LeafGreen you will need to trade it from Emerald.
you find delibird in island number 4 in the snow caveDelibird is uncatchable in leafgreen get one from firered.