How to add another page to vuepress blog?

Question

I want to add another page to vuepress with the blog plugin.

The new page that I added does not show the content.

I expect the about page to show the content

I use basic vuePressBlog template. My tree structure is

├── examples
│   ├── about
│   │   └── Readme.md
│   └── _posts
│       ├── 2018-4-4-intro-to-vuepress.md
│       ├── 2019-6-8-intro-to-vuepress-next.md
│       ├── 2019-6-8-shanghai.md
│       ├── 2019-6-8-summary.md
│       └── 2019-6-8-vueconf.md
├── index.js
├── layouts
│   ├── GlobalLayout.vue
│   ├── Layout.vue
│   ├── Post.vue
│   └── Tag.vue
├── package.json
├── package-lock.json
└── README.md

I added the following lines to the ./example/.vuepress/config.js

module.exports = {
  title: "SlimBlog",
  theme: require.resolve("../../"),
  themeConfig: {
    // Please keep looking down to see the available options.
    nav: [
      {
        text: "Home",
        link: "/",
      },
      {
        text: "about",
        link: "/about/",
      },
      {},
    ],
  },
};

I assume there might be a layout missing but I unable to find the config for this.