Gallery Pages
In case of Demo Contents Import gallery pages are already created and you do not need to follow this section.
Go to Dashboard → Pages → Add New and provide a page title that suit your purpose.
Select the appropriate template from page attributes. As examples are displayed in 3 screen shots below.
If you want to change the default banner then you can do that from Banner Settings meta box displayed in screen shot below.
You can Publish the page once it is ready.
After publishing you need to add the newly created page in menu from Dashboard → Appearance → Menus