In Pokemon Ruby, the surf HM03 is found in Wally’s home close to the Petalburg City Gym. A Pokemon gains new abilities when it uses a Hidden Machine, or HM.
As opposed to Technical Machines, or TMs, HMs provide abilities that can be used on non-combat occasions. Similar to previous HMs, using the power offered is necessary to finish the game entirely.
The next mission is to fight every trainer in the gym in any order after arriving back in Petalburg City on Route 111, and the last battle room is where players will face their own father. After the battle, players can visit Wally’s house next door, where they can speak to his father to receive HM03, or surf.