I need to roll back my website

The first step is to update your WordPress website URL from HTTP to HTTPS. You can do so from Settings → General in the WordPress admin interface.

Then you’ll probably still need to setup a redirect to actually force all traffic to HTTPS. You can do that with .htaccess rules like these:

If that seems a bit too dangerous to you, you can also use a plugin like Really Simple SSL to setup the HTTPS redirects too.