It's a hack (I think) of FireRed or LeafGreen. So, it must be in the Safiri Zone! In the Back is where you can find the guy who gives you the HM Surf!
You surf on pokemon in blue lakes or oceans.
You'll have to find it in the Safari Zone somewhere in a house.
solar cave
I believe it is in Solar Cave...
go to Pokemon then press the Pokemon that knows surf press surf that's how u do it!
You surf there.
Find a Pikachu on red or blue, find the surfing hm, teach it surf, trade pikachu with another pokemon, and you have a surfing pikachu.
seafoam islands, surf to the right of cinnabar. to find a walkthrough for the caves of the islands, try googleing them
In the Safari Zone
Surf is found in the depths of the Safari zone in Fuschia city (Koga's Gym).
whooper,quagsire,um...any water type pokemon!
Surf south from Pallet town and find Blue on Cinnabar Island.