Private links work by anonymizing your Cal.com user information. All private links are single-use and regenerate after they are used. This is one of the ways in which they help to protect your information.
You can use private links with both public and private events. To activate and use private links, you have to first access the settings of the event in question. This is done in the same way you would edit an event.
Simply click on the event from within the event type dashboard. Once this is done, choose the advanced tab and then scroll down until you see the setting named "Enable private URL."
Simply click on the toggle so that the setting is now in the active position. You will now see an anonymized URL that you can share via email or online. As always, don't forget to click the save button in the upper right-hand corner to finalize your changes.