If you need a custom page template in Magento2, outside the standard 1column, 2column-left templates, you can make one quite easily by adding a layout.xml in your Magento2 theme.
You will see as follows:
- xml (this defines the new template, in this case, a new homepage template)
- page_layout/custom_home.xml (this is the layout for the new template, here you can see we have added a .phtml template which can be used if needed)
- templates/html/home.phtml (this is the custom .phtml template if needed).
If you would like further info drop me a call on 0161 237 3114 or an email (email@example.com) and I can send you more code examples etc.