Frontend Hack's tutorial on displaying the first image from an ACF repeater field in WordPress provides a practical PHP snippet. It guides developers on how to retrieve a repeater field named ‘photos’ and display the URL of the first image. The tutorial explains the process of checking if the repeater field has any rows, iterating through them, and extracting the URL of the first image while ensuring there are no PHP errors. Frontend Hack offers a variety of HTML, CSS, and JavaScript resources for developers.