1. For encoding, input the message in the message box:

 

2. Set the encoding options:

 

3. Enter a key:

 

4. Encode the message:

 

5. Convert output to all uppercase:

 

6. Double key encryption:

 

7. Encode with the two keys:

 

8. For decoding, input the encryption in the message box and the supply key:

 

9. Choose the proper decoding options:

 

10. Decode to get the message: