DNN Platform 7.3+
DNN Evoq Content 7.3.4
DNN Evoq Engage 7.3.4
DNN Evoq Intranet 7.3.4
Create new theme or select existing theme from style switcher.
Select "One Page" website type and hit Save from style switcher.
Open the page you want to make One Page and apply your one page theme to the page (Edit Page > Page Appearance > Page Theme).
Add the HTML Module on the page.
Wrap the HTML content with any html tag with Id attr should name as appropriate menu name.