These notes are from the Course 1 - Unit 8 Project from Introduction to Unity for 2D Video Games. They should help to re-create the project from scratch as they highlight the main points of the lesson.
Is a good practice to stablish your own folder structure and try to keep it as stantarized as possible for your different projects and types of games.
It's recommended to set this structure as soon as your project is started. Here's a basic custom structure for a 2D Game: