The link below opens an article that contains the following information:
- Lessons interface
- Creating a unit
- Creating a lesson
- Creating new material
- Linking to external resources
- Embedding versus linking to external resources
- Setting material as optional or required
- Adding existing material
- Replacing uploaded files
- Arranging, editing and deleting materials
- Posting materials to your course homepage
Link: Add and organize learning materials in the New Content Experience