Click the Slide Sorter View button.
Click the slide you want to delete.
Press the Delete key on your keyboard.
PowerPoint removes the slide and renumbers the other slides automatically.
After reviewing your slides in Slide Sorter view, you might need to remove a slide you no longer need. Just remember, removing the slide removes any information included on the slide.
If you accidentally removed the wrong slide, click the Undo button on the toolbar to bring it back again.