Starting a new page on wiki takes only a couple of clicks and is an important part of contributing to a wiki.
Click on the contribute button on top right of your wiki. Here you will be presented with a dropdown menu where you will see a link to "Add a Page"
The "Create a new article" box will open
You can choose the article name by typing it in the box. This name will become the last part of the page's URL.
Decide between a standard page layout or a blank page. The standard layout provides image and video placeholders as well as section headings. The preload contents for the "Standard layout" are stored at MediaWiki:Createpage-with-video on your wiki and can be edited by local admins.
A second way to create a page is by clicking on any red link on your wiki (which can be created by linking to a page that does not exist). You will then be brought into edit mode where you can add your content.