Update README.md

examples/advanced/xgboost/README.md

@@ -10,6 +10,7 @@ and install the additional requirements:
 ```
 python3 -m pip install -r requirements.txt
 ```
+Also, follow [encryption plugins instruction](https://github.com/NVIDIA/NVFlare/tree/main/integration/xgboost/encryption_plugins) to setup encryption plugins.
 
 ## XGBoost 
 XGBosot is a machine learning algorithm that uses decision/regression trees to perform classification and regression tasks, 
@@ -51,4 +52,4 @@ collaboration, and histogram-based vertical collaboration.
 ### [Secure Federated XGBoost with Homomorphic Encryption](./fedxgb_secure/README.md)
 This example includes instructions on running secure federated XGBoost with homomorphic encryption under 
 histogram-based horizontal and vertical collaboration. Note that tree-based collaboration does not have security concerns 
-that can be handled by encryption.
+that can be handled by encryption.