Get in touch with your sysadmin to publish this site to internet.
The QlikHelp will help you/him/her Home ‒ Qlik Sense
Keep in mind, if you want to the site access, you should allocate a token to your users as well, or grant access pass.
As Gabor mentioned, this is entirely something outside of the control of Qlik Sense. You will need to check with the appropriate folks in your organization to expose a server to the outside internet. Do keep in mind one some of the major hiccups that are
- The availability of the required ports (review Qlik Sense 2.X Ports)
- Support for websockets by any networking devices in front of Qlik Sense