Update DeploymentGuide.md for local development & debugging instructions

Author: Prajwal-Microsoft

docs/DeploymentGuide.md

@@ -229,6 +229,12 @@ This will rebuild the source code, package it into a container, and push it to t
 
      - Follow steps in [Delete Resource Group](DeleteResourceGroup.md) if your deployment fails and/or you need to clean up the resources.
 
-## For local Debugging
+## Environment configuration for local development & debugging
+> Set APP_ENV in your .env file to control Azure authentication. Use dev to enable to use Azure CLI credential, Prod to enable Managed Identity (for production). **Ensure you're logged in via az login when using dev in local**.
 
-To configure your environment, navigate to the `src\App` folder to create a `.env` file based on the `.env.sample`, fill it using deployment output or the Azure Portal under "Deployments" in your resource group, and ensure APP_ENV is set to "**dev**".
+To configure your environment, follow these steps:
+
+	1. Navigate to the `src\App` folder.
+	2. Create a `.env` file based on the `.env.sample` file.
+	3. Fill in the `.env` file using the deployment output or by retrieving values from the Azure Portal under "Deployments" in your resource group.
+	4. Ensure that the `APP_ENV` variable is set to "**dev**".