From the fourth point, Sam can deduce that memories may come with the activation of the system. As he digested the memories, prompts appeared, but these prompts seemed to be from another system designed to activate something else.
About the system, Sam gleaned information from the novel. He had absorbed all the memories of the figure, gaining knowledge about the figure's life from birth to death. During that process, Sam discovered that the figure had also read many novels. This allowed Sam to deduce various aspects related to the figure's conspiracy and existence. Sam felt a sense of confusion, but he brushed it aside, recognizing that it was of little consequence. After all, he had received an invitation to activate another system.