When you start the gmae, you will get a notification at the top of the screen that tells you to see your Mentor. In his study he will give you a lesson and you must pick up a book from his library (click on the bookshelf in his study).
When you have done this, you will receive a notification telling you where to go for your next negotiation. For example, in the first case you will see this message: "Teo is waiting for you at the dock". If you click on the notification, it will take you directly to the correspondant scenario and you can start negotiating by clicking on the character.