Hi there,
adding a valid ID to your Section should not break the styling unless it is an ID that is already being used. Can you add an ID to one of the sections so i can see whats up?
For a navigation menu link you would create a custom link, with a url like so:
https://www.yoursite.com/the-page-link-is-on/#sectionID
sectionID
should be the same as the ID label you gave the section.
E.g I give one of my sections an ID of challenge
my URL looks like:
https://www.yoursite.com/the-page-link-is-on/#challenge