First time couldn’t find solution so I need to ask for a help:
Each .nav-link should have text that corresponds to the header text of its related section (e.g. if you have a “Hello world” section/header, your #navbar should have a .nav-link which has the text “Hello world”).
Each .nav-link should have an href attribute that links to its corresponding .main-section (e.g. If you click on a .nav-link element that contains the text “Hello world”, the page navigates to a section element with that id). My code