You can use the keyboard shortcut Ctrl+C to copy the slide and Ctrl+V to paste it.
You can also delete a slide by pressing the Delete key on your keyboard.
In the bottom-right corner of the PowerPoint window are three view commands. From here, you can change the view to Normal, Slide Sorter, or Slide Show view by clicking a command.
Normal is the default view and where you will create and edit your slides in the center slide pane, and all of the slides will appear on the Slides tab in the left task pane.
Slide Sorter is a view of your slides in thumbnail form. The slides are presented horizontally, which allows you to see more slides at the same time.
Slide Show view fills the computer screen with your presentation so you can see how the presentation will appear to an audience.