The menu “sliding” the one-page

[ Moderator note: moved to Fixing WordPress. ]

Hi,
I’m now trying to create a website containing just one page, however I want it to have the menu that takes the user to the chosen section of this one page. I mean something like here:
https://themehunk.com/wp-themes/oneline-lite/

or here:
https://www.uipasta.com/wordpress-preview/rolling/

I’ve been trying to do this with a few themes (also with the two above), but I wasn’t able to create something like this with any of them. So my question is how to do it?
I’d know how if I was just using HTML, but probably there is some simplier option and thius is what I’m looking for. Any ideas? ??