still need help-images inside wp-content/ uploads/ are not showing up in my media library and uploaded using FTP protocol

It looks, that there is a problem in your database, even more possible when you got “could not insert post into the database”.

Have a look into your database, go to the wp_posts table and inspect entries with post_type “attachment”. Here are the attachments saved in your database.

Pick several attachments and write down their ids. Then go to the wp_postmeta table and search the “post_id” with the id you wrote down. You should get additional information about the attachment, like the location of the file, etc. Are you getting those details correctly?

One more thing, make sure, that the database user has enough privileges granted for a selected database – this can be ofter set through cPanel or through some other hosting management dashboard.