attribute nofollow,

Good day.
Could you please advise how to make sure that in Drupal 8, when navigating through the menu using the Superfish module, link juice is not passed—i.e., how to insert a nofollow tag? Also, how to prevent Drupal itself from adding links to the login page for registration and in the book output? Otherwise, you end up with hundreds of links on every page that leak link equity.