The Tag Options tab on the right side will allow you to tag individual images and group them together.
Clicking the Arrow, or double clicking the "Tag Options" will collapse the well for more viewing space.
Clicking the Heart in the Tagging menu will set the selected image as a Favorite. You can do this with each individually, or with multiple images selected.
Clicking the Heart again will remove the Favorite status.
Assigning a Star ratings can also be done both individually or with a group of selected images.
Clicking the same star again will remove a rating.
Tagging for Type of Image
Your first tagging options are for placement preferences, if the image should be used as a Main image on a page, the Cover, or as a Panorama across the spread.
This can be done with images individually or when selected as a group.
Clicking the preference again will remove the designation.
Selecting multiple images together and choosing the "Group" option will link these images together. These images will always be group together on a spread, dragging just one will bring them all. This will apply in Auto Design as well.