If you want to restrict access to directories on your website, you can use your hosting account's built-in password protection feature.
Note: This feature does not offer a typical member login experience like a bank or retail site. Features like that require databases and are much more complex.
After protecting the directory, you need to add users that can log in to it.
Now, when browsing to that directory, only visitors that can enter a username and password combination can view its content.