The Slide Master feature in Microsoft PowerPoint helps with the consistency of your slides, especially if you want the same fonts, headings, and colors for all your slides in your presentation.

Use the Slide Master view in Microsoft PowerPoint to customize the look and feel of your slides and create a consistent view for your presentation. You may wish to create multiple master slides ...

You can add page numbers to your PowerPoint slideshow through the "Slide Master" page, which lets you edit your entire slideshow at once.