If you wish to hide.php extension from your website, then create a .htaccess file in your project root and paste the following code :
RewriteEngine On
RewriteCond %{THE_REQUEST} ^[A-Z]{3,}\s/(.+)\.php[^\s]* [NC]
RewriteRule ^ /%1 [R=301,NE,L]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}.php -f
RewriteRule ^ %{REQUEST_URI}.php [QSA,NC,L]