Please take the back up of the current files and re-install your WordPress, themes and plugins.
Keep only your database (already in place there on the server), your /wp-content/uploads/ folder and any *customized* theme or child theme in /wp-content/themes/, but delete everything else other than wp-config.php and then use only fresh downloads to re-build your installation. Any help available from anyone here at the forums can happen only right here at these forums, and you are welcomed to post as many questions as necessary while rebuilding your installation.