Can someone help me how to disable wp-content/plugins?
if i have already disable it,can someone know if i use nulled plugin?

http://www.blackhatworld.com/blackha...e-plugins.html

Do you mean hide the content of the folder?
You can use the cpanel 'index manager' feature ( it will create a .htaccess file ) or you can create an empty index.html file.
Hope this will help you !