I am trying to password protect a subdomain and all of it's subdirectories and files, but my knowledge on the matter is very limited, how can I go about doing that?
It's a simple two step process
In your .htaccess put
AuthType Basic
AuthName "restricted area"
AuthUserFile /path/to/the/directory/you/are/protecting/.htpasswd
require valid-user
use http://www.htaccesstools.com/htpasswd-generator/ or command line to generate password and put it in the .htpasswd
Note 1: If you are using cPanel you should configure in the security section "Password Protect Directories"
EDIT: If this didn't work then propably you need to do a AllowOverride All
to the directory of the .htaccess (or atleast to previous ones) in http.conf followed by a apache restart
<Directory /path/to/the/directory/of/htaccess>
Options Indexes FollowSymLinks MultiViews
AllowOverride All
</Directory>