How can I add , at example, “2019-03-13-” to my page slug (would be useful for news or blog pages or something similar), after saving page, automatically? And get this value from my “date” field at example.
Yes, the number (when publishing a page) doesn’t become part of the URL. What you could do, however, instead of adding the date to the slug, is use a route to catch a URL with the date in it and return the corresponding page.
To actually print that URL when linking to that page, you can change the URL method in a page model.