Add guide for README.md

README.md

@@ -3,13 +3,65 @@
 -   Default Encryption
 -   E2E Encryption
 
-### Generate for Default Encryption
+### How-to-use
+
+-   Default Encryption Provider
+
+```ts
+const key = "67rKmuc6DiDukE0jsUP421Eizo4CreaL6Q7Pg/NmH/s="
+const iv = "FEFM9AY2m5jDq6GZ+CfLIA=="
+const text = "Hello World"
+const provider = CryptoProvider.newInstance(
+    new DefaultCryptoProvider({
+        key: key,
+        iv: iv,
+    })
+)
+
+const encrypted = provider.encrypt(text)
+const decrypted = provider.decrypt(encrypted)
+
+// Output
+console.log(text) // "Hello World"
+console.log(decrypted) // "Hello World"
+```
+
+-   E2E Encryption Provider
+
+```ts
+const PRIVATE_KEY_VALUE = "-----BEGIN RSA PRIVATE KEY-----"
+const PUBLIC_KEY_VALUE = "-----BEGIN RSA PUBLIC KEY-----"
+
+const text = "Hello World"
+const provider = CryptoProvider.newInstance(
+    new E2ECryptoProvider({
+        publicKey: PUBLIC_KEY_VALUE,
+        privateKey: PRIVATE_KEY_VALUE,
+    })
+)
+
+const encrypted = provider.encrypt(text)
+const decrypted = provider.decrypt(encrypted)
+
+// Output
+console.log(text) // "Hello World"
+console.log(decrypted) // "Hello World"
+```
+
+### Generate for Default Encryption (Key and IV)
 
 ```js
 const key = crypto.randomBytes(32)
 const iv = crypto.randomBytes(16)
 ```
 
+### Generate for E2E Encryption (Public and Private Key)
+
+```shell
+openssl genrsa -out rsa_4096_priv.pem 4096
+openssl rsa -pubout -in rsa_4096_priv.pem -out rsa_4096_pub.pem
+```
+
 ### Contributors
 
 -   Sambo Chea <sombochea@cubetiqs.com>