Open your Google Slides presentation.

Click on "File" in the top menu and select "Publish to the web".

In the pop-up window, go to the "Link" tab.

Check the box for "Start slideshow as soon as the player loads".

Adjust the slide advance timing using the dropdown (e.g., every 3 seconds).

Click "Publish", then copy the generated link.

Share the link or open it in a browser to see the slides play automatically.