Not able to add or view plugins or posts section in wordpress admin panel

I am facing an issue where I am not able to add new plugins or posts. Whenever I am clicking on adding new button it always redirecting me to the home page.

I tried disabling the theme and plugins but nothing helping me to solve this issue.

Any idea how to solve this issue.

The problem could be the installation or server side problem. At this point, there’s not much things to offer except a paid support