From local command console type:
cat ~/.ssh/id_rsa.pub
If you see a string starting with ssh-rsa you already have an SSH key pair otherwise you have to generate it.
EX: ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAAAgQC8PAgJVXMQysVOuI0znKGXaUNqdk4reejNPKlG+/RZ+B47YWmiL/qIFx6ILjLQa8iRMmAj9n3hRGBQoIQnU0ZzickuQ/AJi4cEr2+4Hm6I3QTqodWGOijRBXjhGoToIGAAu1ymM+zNSMMtBvMhaOl8QUFY4dAb6YyZs/gvnWKczw== mac@macs-MacBook-Pro.local
in the user profile add a ssh public key
Don’t paste the private part of the SSH key. Paste the public part, which is usually contained in the file ‘~/.ssh/id_rsa.pub’ and begins with ‘ssh-rsa’