Fix link to create-next-app docs (#16069)

Fixes #16066

docs/getting-started.md

@@ -29,7 +29,7 @@ yarn create next-app
 
 After the installation is complete, follow the instructions to start the development server. Try editing `pages/index.js` and see the result on your browser.
 
-For more information on how to use `create-next-app`, you can review the [`create-next-app` documentation](/docs/create-next-app.md)
+For more information on how to use `create-next-app`, you can review the [`create-next-app` documentation](/docs/api-reference/create-next-app.md)
 
 ## Manual Setup
 

docs/manifest.json

@@ -191,6 +191,10 @@
       "heading": true,
       "routes": [
         { "title": "CLI", "path": "/docs/api-reference/cli.md" },
+        {
+          "title": "Create Next App",
+          "path": "/docs/api-reference/create-next-app.md"
+        },
         {
           "title": "next/router",
           "path": "/docs/api-reference/next/router.md"