Before you start
Create the Product Group and add the correct products before assigning the group to users.
Assign a Product Group
Open User Logins.
Select the user you want to update.
Choose the update option.
Find the Product Group(s) field.
Select one or more Product Groups from the drop-down list.
Select Save and Close.
What happens next
The user will only see products included in the Product Groups assigned to them, unless their profile is set to ignore Product Groups.