After successful activation every time you add #hide-this-link to a link, the plugin will replace it with an hidden link.
For example, for an URL as https://sample-link.com you should write https://sample-link.com#hide-this-link. Then you will still be able to click on the link, but robots will not see it because Hide Link will replace the link tag with a span and make it clickable with a line of JavaScript.
With the PRO version the links can be hidden also by CSS class, and you have also the options to hide all the links of the navigation.