chore: update README for mockedFrontend

Author: jatZama

README.md

@@ -26,6 +26,10 @@ The server listens on [http://localhost:5173/](http://localhost:5173/)
 npm run build
 ```
 
+## Using the mocked coprocessor for front end
+
+As an alternative to use the real coprocessor deployed on Sepolia, to help you develop your dApp faster and without needing testnet tokens, you can use a mocked fhevm. Currently, we recommend you to use the `ConfidentialERC20` dApp example available on the [`mockedFrontend` branch of this repository](https://github.com/zama-ai/fhevm-react-template/tree/mockedFrontend). Follow the README on this branch, and you will be able to deploy exactly the same dApp both on Sepolia as well as on the mocked coprocessor seamlessly.
+
 ## Documentation
 
 For more information about fhevmjs, you can [read the documentation](https://docs.zama.ai/fhevm).