Remember: you should use the Camera, Book and Quill, and Lectern to provide some synopsis of the project or what's going on near the spawn point. You may also use the NPC to provide guidance for the player, but not using the NPC increases the feeling of isolation for the player.
This is a Myst-style puzzle adventure. If you've ever done an escape room, particularly a really good one, think about expanding that to a whole building / island / world. Use building, coding, command blocks, and redstone to create a game in which the player must solve complex riddles / puzzles / mysteries in order to move forward in the narrative / escape.
You'll probably need:
An environment that naturally or unnaturally confines the player unless specific conditions are met.
Slates, posters, boards, & signs to communicate with the player providing:
Clues
Back Story