From the main_files/wp folder, you will get a extend-wp-json-api.zip file.
Go to your WordPress Admin Dashboard > Plugins > Add New > Upload Plugin.
Upload the plugin and activate it.
After that, You will see a Top Stories Menu option at the left bar of your WordPress admin dashboard. You can control and customize the app with that.
If you are using any cache plugins like LiteSpeed Cache or others then clear the cache after saving the configuration.