To create a new page, simply change URL to page's snake case, e.g. new_page.
To create a new page in some “category”, simply prefix it with category name followed by a colon, e.g. some_category:new_page. See Namespaces for more info.
It's recommended to use Title case (Specifically the Chicago Manual of Style flavor) for headlines. Vercel's title.sh is a good tool for this.