i think there is a guy in solaceon town who will do that
At fuchsia city if you go to the Pokemon center the house to the left of the Pokemon center is the move deleter's house.
go to lilycove city and go right from the pokemon center go up the stairs and in the house with the sign and talk to the old man.
the one with the boat
you have to find the man that deletes any move
move deleter in lilycove city
"Talk to the move deleter."
find the move deleter but i dont know where he is
The HM Strength is found near solacalon town. route 209 is under it. There is a building called the Lost Tower. Go to the top storey and talk to people. You will get the HM Strength.
Go to the Move Deleter in Canalaeve City. He will make your Pokemon forget any moves and is the only way to forget HM moves. If you want a move back (not including TMs/Hms) go to the Move Relearner in Pastoria City with a Heart Scale, which can be found underground.
You have to get a pokemon that can learn the hm surf and u go up to water and press A, then it will say surf, press A and swim! to get off just go to land or fly.
Its impossible to erase a "HM" Becuz it has to be obtain in order to finish the story of the game.
hes in lilycove city at the first top house hes good for hm moves