There is no featured content to be displayed in the slider. To set up the slider, go to Appearance → Customize, and add a tag under Tag Name in the Featured Content section. The slideshow will then display all posts which are tagged with that keyword.
There are no widgets to be displayed. Please go to Appearance → Widgets and add at least one widget to the "Magazine Front Page" widget area. You can use the three Category Posts widgets to set up the theme like the demo website.