To create single page template in Joomla, you need to follow given steps:
1) Firstly add article from Joomla admin -> Content -> Articles -> Add new article.
2) You need to create article in section and you have to assign id for section like <section id="home">Your content
3) Now you have to make menu from Joomla admin -> Menus -> Add new menu item -> Menu Item type -> System links -> External Link.
4) Now you have to link name that you have assigned id in section i.e #home.
Same as you can create multiple sections in content and assign id to sections.