docs: add more description to env

Author: iamjoel

README.md

@@ -4,11 +4,15 @@ This is a [Next.js](https://nextjs.org/) project bootstrapped with [`create-next
 ## Config App
 Create a file named `.env.local` in the current directory and copy the contents from `.env.example`. Setting the following content:
 ```
-# APP ID
+# APP ID: This is the unique identifier for your app. You can find it in the app's detail page URL. 
+# For example, in the URL `https://cloud.dify.ai/app/xxx/workflow`, the value `xxx` is your APP ID.
 NEXT_PUBLIC_APP_ID=
-# APP API key
+
+# APP API Key: This is the key used to authenticate your app's API requests. 
+# You can generate it on the app's "API Access" page by clicking the "API Key" button in the top-right corner.
 NEXT_PUBLIC_APP_KEY=
-# APP URL
+
+# APP URL: This is the API's base URL. If you're using the Dify cloud service, set it to: https://api.dify.ai/v1.
 NEXT_PUBLIC_API_URL=
 ```