Adding an image into the editor:
You can add an image as it's own content type - select 'image' from the content types when adding an article.
Or add it into a rich text article directly.
Adding a PDF into the editor:
Adding a video into the editor:
You can add a video as it's own content type - select 'video' from the content types when adding an article.
Or add it into a rich text article directly.