To create any page, just type that page address into your address bar, if the page wasn't created, you'd be prompted the option to create a new page.
There are namespaces you should keep in mind when creating a new page. The main namespace aka /wiki/*insert page name here* belongs to wiki articles, your personal pages should not be created there. If you wish to create pages for personal uses, please use your own namespace /wiki/User:Rk98/*insert page name here*
Pages under your own namespace cannot be edited by anyone but yourself and the admins. If you wish to create public test pages that can be edited by other people, you should use the sandbox namespace (which is a namespace exclusive to this wiki and not on the list above) located here /wiki/Sandbox/*insert page name here*