Follow the blog post Debugging Node.js apps on Azure App Services to enable debugging and Debug Node.js Web Apps on Azure to start analyzing. This article is another Node.JS troubleshooting guide you can review. Also make sure you have your node start command under Application Settings.
Node-RED appears to be a Windows Service which you won't be able to install on an App Service. You'll have to consider an App Service Container app that will allow more control of OS configuraiton.
Hope this helps.