If you installed TheTis demo data, you don't need to create a new Home Page, you just need to choose from the list Home Pages that were automatically created from the demo content, following these steps:
Go to Settings → Reading.
From dropdown, select which page you want to set as "Front Page" and which page you want as “blog posts” page. Default Front Page is 'Home' and default posts page is 'Blog'.
Click Save Changes
