How To Create One Page Site
Follow these steps to create one-page websites:
First, you should have a section for each part of the page so you can have good functionality in this type.
Also, you need to create a header and sticky header. Follow this link for creating header: This link
To create a page, please create a section and by editing the section, go to Class & ID tab, and put a valid ID. This ID can contain all the characters, numbers and underline characters. (Please note, do not use # in ID field).
Create sections and contents within. After completing the page and putting the unique IDs to each section, save the page.
You will something like this:
Now go to Appearance > Menus and create a new menu
For creating menu for one page, use Custom Links item
Instead of a URL which starts with http:// put the formula #SectionName. According to the image, use # instead of URL and use the section name for scrolling without any space.
You can put any character without any limit in Link Text field
By clicking on Add to Menu, you can create an item menu for each section you have created on your page
Now you can set your menu for the header you have already created.
Please check this link on how to create header: This link