Access to files and folders in var/www are forbidden, what should i do?

on whonix,i installed a webserver (lighttpd) and then configured tor to set up a hidden service, after that i installed php to run .php files, but now when i try to run the install.php file in var/www folder through tor browser, i get the error "403-forbidden"
how should i change permission of this folder? so that i can navigate through installation? the only file accessible now is the index.lighttpd.html.