Um ... You're completely misunderstanding what SSL / HTTPS is and how it works, as well as how Zen Cart works.

a) Your hosting company has given you an SSL address for your site, often at: https://your_domain.com (it could take other forms, as mentioned in the tutorial above)
b) You need to make sure the HTTPS_SERVER setting in your Zen Cart configure.php files contains THAT address.
c) and to tell Zen Cart to take advantage of SSL, you need to tell it to do that, by setting the ENABLE_SSL to true.

That's what the tutorial article I mentioned is showing you how to do.