You can add new documents to the game from the Project View right clicking Create/Horror Engine/Document

On this new Scriptable Object you can set the different pages text and the different sounds used when it’s shown.

Similarly to adding item pickups, adding this document to the game is as simple as dropping the prefab PickupDocument into the level, located in HorrorEngine/Prefabs

Assign the DocumentData property on the PickupDocument component and add the desired model in a way that’s reasonably covered by the Interaction trigger. Optionally, save the new PickupDocument as a prefab variant.