Walkthrough

1. Speak to Professor Tangrowth about a wall of rocks. He will ask you to break them to see what lies beyond.
2. Use Rock Smash on the rocks to open up a path.
3. Follow Professor Tangrowth to a tall structure that resembles a lighthouse. Interact with the console at the base of the structure and listen to the first set of instructions.
4. Speak to Professor Tangrowth one last time to unlock the Do the…Team Initiation Challenge request.

Walkthrough source: Game8.