This blog will teach how to convert the PEM file to a PPK file
1. Run Puttygen.
3. In the dialog, locate the pem file and “Open” it.
4. If required Change the comment from ‘imported-openssh-key” to a something more descriptive like “my-db-server”
5. Optional: Enter a passphrase.
6. Create PPK file by clicking on “Save private key”