to get old rod go to dewford town, then to get good on rod route 118 talk to a fisherman, to get super rod go to mosdeep look in all houses
MAMACITA257:
Go to Dewford Town all the way at the bottom, by the gym. There should be a man in a hat. Talk to him, and he will give you an old rod.
every time you see it say got a nibble press a and soon you will hook a Pokemon
By fishing
Once you get a fishing pole, you enter your bag select pole or rod near water then throw pole in water wait for it to say, (...oh! a bite) then you press A this may take several times.
you go to the docks near jubilife city go back into the house talk to the fishermen he will give you a fishing rod
First of all it depends on what route your fishing in but you catch these pokemon: Magikarp, Staryu, Carvanha, Horsea, Psyduck, Goldeen.
every time you see it say got a nibble press a and soon you will hook a Pokemon
By fishing
Once you get a fishing pole, you enter your bag select pole or rod near water then throw pole in water wait for it to say, (...oh! a bite) then you press A this may take several times.
in the somewhat tall grass. or when you are fishing with a fishing pole. or when you run into a Pokemon when surfing on water.
at jubilife or enterna city
magikarp
you get it in the house on silence bridge
yes you do need a fishing pole to catch mitotic in Pokemon black but you cant catch that Pokemon you have to catch the first evolvation and then you train it until in evolve into a mitotic
go to oldale and at the top there will be a fisher select him
in water by fishing, surfing or diving, and in water institute.
go to the lake of rage
Heck if I know!! Haha