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In this tutorial, I will try to override the gdlr-page-item.php in: \wp-content\themes\totalbusiness\include\function\gdlr-page-item.php from the Total Business theme into the child theme.
In the child theme, copy the file in the path: totalbusiness-child\include\function\gdlr-page-item.php. (create the folder that’s not available in your child theme)
In the functions.php in the child theme, add a line of code:
include_once(get_stylesheet_directory() . '/include/function/gdlr-page-item.php');
Try to make any change in the totalbusiness-child\include\function\gdlr-page-item.php and check it again.