You have successfully set up a webhook endpoint in Node.js using Express to receive inbound SMS messages from Vonage, exposing your local server's endpoint as a public URL for development purposes with the help of ngrok. You can now send and receive SMS messages through this setup, allowing you to handle incoming messages and log their details. The process involves defining a webhook endpoint, setting it up in Vonage settings, writing code to handle POST requests with Express, and using ngrok to expose your local server's endpoint as a public URL.