Let me takes here a note about what is needed to connect through ssh from the phone to an ssh server. A good up to do this is termux. But if the ssh server requires connection through ssh-key, these are the needed steps

• Open termux app on your phone
• pkg install openssh
• ssh-keygent-t rsa
• You will get the key in /data/data/com.termux/files/home/.ssh/id_rsa
• Move the public key to the server and you will be done