Like every single chapter apart of Detective Pikachu, you will be able to activate a variety of different Pika Prompts during the ninth chapter of the game. Some of these Pika Prompts have certain location requirements found in this chapter, while some you can activate by doing nothing special at all. In total, you can obtain 11 Different Pika Prompts during the ninth chapter of the game. Below is a list of all said Pika Prompts, along with the requirements for each.
Rush To The Agency (Ryme City): No Special Requirement
Pikachu's Resolved (Ryme City) Be Near Ludicolo
Where's The Scene Of The Crime (Baker Detective Agency): No Special Requirement
Find The R Dispersing Machines (Central Square): No Special Requirement
The Clock Tower (Central Square): Be Near The Clock Tower
Do Your Best! (Central Square): No Special Requirement
Calm Down (Central Square): No Special Requirement
The First R Dispersing Machine (Central Square): Find The First R Dispersing Machine
The Second R Dispersing Machine (Central Square): Find The Second R Dispersing Machine
The Third R Dispersing Machine (Central Square): Find The Third R Dispersing Machine
Who's The Mastermind? (Central Square): Discover Keith Isn't Working Alone