Hide url in subdirectory install?
Add this rewrite rule in your .htaccess file:

RewriteEngine On
RewriteRule ^/subfolder/(.*)$ http://www.example.com/$1 [L,R=301]


Change subfolder and www.example.com.

Also, you can try with this:

RewriteCond %{HTTP_HOST} ^www\.(.+)$ [NC]
RewriteRule ^ http://%1%{REQUEST_URI} [NE,R=301,L]

RewriteCond %{HTTP_HOST} ^(www\.)?example\.com$
RewriteRule !^subfolder/ /subfolder%{REQUEST_URI}  [L]


Again change you domain and subfolder name.