I have a landing page that is linked to a product category page, when i changed its permission by removing read access for everyone i still see the link in the subnavigation.
Is there a way to make a page/product category only visible to a group of user?
A landing page is a way to add blocks to a category page. So if you change the permissions on the landing page so that only group Example has access, only persons in that group will see the additional blocks when visiting the category. It doesn’t affect who can see a specific category altogether.
If you want to limit access, you can do something similar to your thread about products. A common way to control which customers can see which products is to use price lists.