Go the the Posts menu in your WordPress administration. Select a post to edit. In the “Document” boxes, you will see VIP checkboxes, one for each VIP Lounge. Check the boxes for which you want to restrict the post visibility.

If nox chekbox is checked, the post is visible for everyone.

If your post is linked in a WordPress Menu, the menu entry point will also disappear for users not allowed to see the post.