PHP and other scripts needed on server for WordPress?

Hi, I am running a WordPress website on a hosting account using Direct Admin control panel.

The problem is that when I update things on my site,upload images, or import mySQL databases, I get the errors posted below… I think it might be a problem with scripts that are not installed on my Direct Admin control panel.

I have check that PHP is working and permissions are set correctly.

How can I find out what the problem is? …Or what scripts need to be installed on my server for WordPress to work correctly, if that’s the problem?

Any advice is appreciated. Thanks

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Method Not Implemented
POST to /wp-admin/media-upload.php not supported.

or

Forbidden
You don’t have permission to access /wp-admin/post.php on this server.

or

Forbidden
You don’t have permission to access /phpMyAdmin/import.php on this server.

or

Bad Request
Your browser sent a request that this server could not understand.
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