Install agent-transfer by entering the following commands in the terminal:
sudo apt update sudo apt install agent-transfer
copy a secret key from GnuPG's gpg-agent to OpenSSH's ssh-agent
agent-transfer is a simple utility to extract a secret key from GnuPG's gpg-agent and send it to a running ssh-agent. This is useful for those who prefer the runtime semantics and behavior of OpenSSH's ssh-agent, but whose secret keys are held in long-term storage by GnuPG's gpg-agent. . This tool comes from the monkeysphere project.