You can limit access to certain products to the members of specific groups. There are 3 different ways to restrict access to a product:
Method 1:
You can limit access to the Category containing the product. This method is simplest when you want to place the same access limits on all the products in a group.
Method 2:
When editing the configuration of a group, you will see a multi-select field labeled Visible Products. By checking any of the boxes for any product, you will limit access to the products to members of that group:
Method 3:
Edit the product Products. In the left-side of the product edit page, you will see a tab labeled "Groups". In the Groups tab, you will see a list of all the different groups in the system. By checking any of the boxes for any group, you will limit access to the product to members of certain groups: