Https is a method to encrypt information in transit and in no way does it apply to securing a server! By default TCP port would 443 while unsecured would be 80. This SSL certificates can be created via Linux using such tools as OpenSSL If I am not mistaken its free.
Password protect, do you mean to restrict a particular portion of your site and to use a password as a form of authentication? If you so, you always use .htaccess to configure that kind stuff.
Now, securing a server. I mean physically securing your server say you have your dedicated box. There are a lot of factors to take into consideration. Your OS, what level of security you want and such.
It could be as simple as blocking specific ports on your server to a more complex task such as to lock down PHP and use mod_security with apache or securing your TMP partitions.
An SSL certificate associated with your website. SSL (Secure Sockets Layer protocol) is a standard for transmitting confidential data such as credit card numbers over the Internet. Most true business sites support this feature which allows more security in data transmitted over the web. SSL uses a private key to encrypt data that is transferred over the SSL connection.
You need to make sure, that you get dedicated IP, as the SSL requires dedicated IP, as name-based hosting does not support data encryption in HTTP requests.
The H-Sphere control panel allows you to use the certificate you already have or create a temporary certificate and then acquire a permanent certificate from a trusted authority. You can use Shared SSL certificate instead of purchasing a certificate of your own.
If it is allowed in your plan, you can also buy and install a permanent Comodo Certificate directly from your CP.