At the 100% pass rate of Surfing 1, there is a bird shooting game.

Shoot the bullseye to start the game, then shoot as many birds as possible.

After the time is up, shoot the bullseye of the apple.

Collect the apples under the tree on the right.

Repeat the above process until you have collected enough apples. The slot machine is at the door.

At the 77% pass rate of Surfing 2, you will come to a platform with an elevator.
Take the elevator up and you will find a boss waiting for you.
After defeating the BOSS, don't go straight, go left.
Look down at the edge and you will see the platform you just came up from by elevator. Jump down.
Take the elevator up again, and you will find that the BOSS has resurrected.

Repeat the above process, and you can get 2 coins each time you defeat the BOSS.

If the achievements do not unlock after collecting enough apples and coins, return to Frozen Beach, restart the game and load the Frozen Beach save.