Need help with linux ubuntu running virtual box to use openssh

I am trying toSet up OpenSSH on LInux machine running on virutal box so I can log in to my machine using a public/private key instead of a password
have already got the private public keys by running this cmd in terminal
mkdir ~/.ssh
chmod 700 ~/.ssh
ssh-keygen -t rsa
verify open ssh was running by ps -A | grep sshd
verified it was listening to port 22 by sudo ss -lnp | grep sshd
next i log in using my own computer ssh -v localhost then it ask for my password so i dont know what i am diong wrong here and this is what i need help on i am sure its easy for a linux pro