To add slide numbers, page numbers, or the date in PowerPoint, you can follow these steps:

1. Open your PowerPoint presentation.
2. Go to the “Insert” tab on the ribbon at the top of the window.
3. In the “Text” section, click on the “Header & Footer” button. This will open the Header and Footer dialog box.
4. In the Header and Footer dialog box, you’ll see three tabs: “Slide,” “Notes and Handouts,” and “Outline.” By default, the “Slide” tab is selected.
5. To add slide numbers, make sure the “Slide number” checkbox is selected.
6. If you want to customize the appearance of the slide number, click on the “Apply to All” button. This will apply the changes to all slides in your presentation. You can also choose to apply the slide number to only selected slides by using the “Apply” or “Apply to Selected Slides” button.
7. To add page numbers (for printed handouts or notes), switch to the “Notes and Handouts” tab in the Header and Footer dialog box.
8. Select the “Page number” checkbox and choose the desired format from the options provided.
9. Similarly, you can switch to the “Outline” tab to add page numbers to your presentation’s outline.
10. To add the date, go back to the “Slide” tab in the Header and Footer dialog box.
11. Select the “Date and time” checkbox and choose the desired format from the options provided.
12. Once you have made the desired selections, click on the “Apply” or “Apply to All” button to add slide numbers, page numbers, or the date to your PowerPoint presentation.

Note: The steps mentioned above are based on PowerPoint 2019/Office 365. The options and dialog boxes may vary slightly depending on the version of PowerPoint you are using, but the general process should remain the same.