Post Type Switcher
Want to convert an existing WordPress post into a page or vice-versa? The Post Type Switcher plugin makes it easy to switch between a post, page, or any custom post type on your website.
Change Post into a Page in WordPress Dashboard
Post Type Switcher is my all-time favorite plugin from John James Jacoby (Matthew Gerring and Andrew Norcross). After the installation, you will see a new “Post Type” section in the block editor that will allow the automatic conversion of a post into a page or any custom post type registered on your website.

Just one click conversion of a post to page
Just go to edit mode of a post or page you want to switch the post type. Select the post or page option in the “Post Type” section, and it will be converted. If you have converted a post into a page, then that post will appear under pages after the conversion.