Wordpress Add New Plugin Invisible Solution
If the Plugin -> Add New section is not visible or unclickable in your Wordpress system, the reason may be that you have turned off plugin editing via the wp-config.php file.
Open your wp-config.php file and search for the following line in it;
define( 'DISALLOW_FILE_MODS', TRUE );
If it appears, delete this line and save the file, your problem will be solved.
If you are also experiencing file editing problems, you can similarly remove the following line in wp-config.php and save the file and solve your problem;
define( 'DISALLOW_FILE_EDIT', TRUE );