If you are allowed to edit pages in this Site, simply click on edit button at the bottom of the page. This will open an editor.
The easiest way to create a new page is to create a link to it on an existing page and then follow that link. If the page does not exist, it takes you to a page that gives you an option to create it. To create a link to a new page, use syntax: [[[new page name]]] or [[[new page name | text to display]]]. Follow the link to create a new page and instantly edit it!
Creating and editing pages is easy. Don't be shy…
Please visit Documentation pages to learn more.