If you want to build one page navigation, please read our One Page Setup article.
When you’re not using menu items or elements, then you can try adding a custom css class to the anchor tag.
Theses classes are “hash-scroll” and “hash-scroll-wrap“. You can add hash-scroll to a anchor tag directly and hash-scroll-wrap class to its parent tag.
<a class="hash-scroll" href="#section1">Section 1</a>
<div class="hash-scroll-wrap"><a href="#section1">Section 1</a><a href="#section2">Section 2</a></div>
Here “section1” and “section2” are IDs of scrolling elements.