update berrachain readme

berrachain/README.md

@@ -1,7 +1,61 @@
 # Everstake Wallet SDK - Berrachain
 
 ## Getting Started
+
+You can use two different options to implement staking for Everstake validator.
+
+## Option 1: REST API
+
+You can use REST API to call methods which are described in [Swagger](https://wallet-sdk-api.everstake.one/swagger/) with detailed examples
+
+```
+https://wallet-sdk-api.everstake.one
+```
+
+## Option 2: TypeScript library
+
+You can install and import Wallet SDK for Javascript/TypeScript.
+
+### Step. 1: Installing the Library
+
+Install the npm library by copying the code below.
+
 ```sh
 $ npm install @everstake/wallet-sdk-berrachain
 ```
 
+or you can also use yarn
+
+```sh
+$ yarn add @everstake/wallet-sdk-berrachain
+```
+
+or you can use pnpm
+
+```sh
+$ pnpm add @everstake/wallet-sdk-berrachain
+```
+
+### Step. 2: Import Wallet SDK
+
+After installing the app, you can import module Berrachain and use the SDK:
+
+#### Import ES6
+
+```ts
+// import modules
+import { Berrachain } from '@everstake/wallet-sdk-berrachain';
+```
+
+#### Import ES5
+
+```ts
+// import modules
+const { Berrachain } = require('@everstake/wallet-sdk-berrachain');
+
+```
+
+## Questions and Feedback
+
+If you have any questions, issues, or feedback, please file an issue
+on [GitHub](https://github.com/everstake/wallet-sdk/issues).