How to Use Encrypt a Message:

When prompted, select Encrypt by typing e. Enter the text you want to encrypt (e.g., "Hello, World!"). Provide a shift value (e.g., 3). The program will display the encrypted text. Decrypt a Message:

When prompted, select Decrypt by typing d. Enter the encrypted text you want to decrypt. Provide the same shift value that was used during encryption (e.g., 3). The program will display the decrypted text.