Using the Edit option
To change the URL (also referred to as “slug”) containing the name of your Page, hover over the Page title of the Page in the Pages screen and select Edit.

In the Page Sidebar settings, under Summary click the URL link to open the URL popup. Change the Permalink entry to change the URL of the page.

As you type in a new URL in the Permalink field, you can view the updated Page URL under View Page.

Select Update to save the new URL changes.