revise instruction of setting env for knowledge source data

Author: chienyuanchang

docs/choose-signature-options.png

@@ -0,0 +1,27 @@
+# Set env variables for training data and reference doc for Pro mode
+Folders [document_training](../data/document_training/) and [field_extraction_pro_mode](../data/field_extraction_pro_mode) contain the manually labeled data for training and reference doc for Pro mode as a quick sample. Before using these knowledge source files, you need an Azure Storage blob container to store them. Let's follow below steps to prepare the data environment:
+
+1. *Create an Azure Storage Account:* If you don’t already have one, follow the guide to [create an Azure Storage Account](https://aka.ms/create-a-storage-account).
+    > If you already have an account, you can skip this step.
+2. *Install Azure Storage Explorer:* Azure Storage Explorer is a tool which makes it easy to work with Azure Storage data. Install it and login with your credential, follow the [guide](https://aka.ms/download-and-install-Azure-Storage-Explorer).
+3. *Create or Choose a Blob Container:* Create a blob container from Azure Storage Explorer or use an existing one.  
+   <img src="./create-blob-container.png" width="600" />  
+4. *Generate a Shared Access Signature (SAS) URL:*
+    - Right-click on blob container and select the `Get Shared Access Signature...` in the menu.
+    - Check the required permissions: `Read`, `Write` and `List`
+    - Click the `Create` button.  
+   <img src="./get-access-signature.png" height="600" />  <img src="./choose-signature-options.png" height="600" />  
+5. *Copy the SAS URL:* After creating the SAS, click `Copy` to get the URL with token. This will be used as the value for **TRAINING_DATA_SAS_URL** or **REFERENCE_DOC_SAS_URL** when running the sample code.  
+   <img src="./copy-access-signature.png" width="600" />  
+6. *Set Environment Variables in `.env` File:* Add the SAS URL as value of **TRAINING_DATA_SAS_URL** and/or **REFERENCE_DOC_SAS_URL** and designated folder path as value of **TRAINING_DATA_PATH** or **REFERENCE_DOC_PATH** into the `.env` file. 
+
+    ```env
+    TRAINING_DATA_SAS_URL=<Blob container SAS URL>
+    TRAINING_DATA_PATH=<Designated folder path under the blob container>
+    REFERENCE_DOC_SAS_URL=<Blob container SAS URL>
+    REFERENCE_DOC_PATH=<Designated folder path under the blob container>
+    ```
+
+Now, we have completed the preparation of the data environment. Next, we could create an analyzer through code.
+
+   

docs/get-access-signature.png

@@ -23,7 +23,9 @@
     "\n",
     "## Prerequisites\n",
     "1. Ensure Azure AI service is configured following [steps](../README.md#configure-azure-ai-service-resource)\n",
-    "1. Follow steps in [Set labeled data](../docs/set_env_for_labeled_data.md) to add training data related env variables in `.env`.\n",
+    "1. Follow steps in [Set env for trainging data](../docs/set_env_for_training_data_and_reference_doc.md) to add training data related env variables `TRAINING_DATA_SAS_URL` and `TRAINING_DATA_PATH` into the `.env` file.\n",
+    "    - `TRAINING_DATA_SAS_URL`: SAS URL for your Azure Blob container. \n",
+    "    - `TRAINING_DATA_PATH`: Folder path within the container to upload training data. \n",
     "1. Install packages needed to run the sample\n",
     "\n",
     "\n"

docs/set_env_for_labeled_data.md

@@ -28,9 +28,9 @@
    "source": [
     "## Prerequisites\n",
     "1. Ensure Azure AI service is configured following [steps](../README.md#configure-azure-ai-service-resource)\n",
-    "1. If using reference documents, please set up `REFERENCE_DOC_SAS_URL` and `REFERENCE_DOC_PATH` in `.env` file. You can refer to similar steps in [Set labeled data](../docs/set_env_for_labeled_data.md).\n",
+    "1. If using reference documents, please follow [Set env for reference doc](../docs/set_env_for_training_data_and_reference_doc.md) to set up `REFERENCE_DOC_SAS_URL` and `REFERENCE_DOC_PATH` in the `.env` file.\n",
     "    - `REFERENCE_DOC_SAS_URL`: SAS URL for your Azure Blob container. \n",
-    "    - `REFERENCE_DOC_PATH`: Folder path within the container for reference docs. \n",
+    "    - `REFERENCE_DOC_PATH`: Folder path within the container for uploading reference docs. \n",
     "1. Install the required packages to run the sample."
    ]
   },