Connection to SSH-server is performing by command

ssh %username%@%server%

Where %username% is user name on server, %server% is server name or IP-address.

If you want to be able to log in without typing in your password, first create ~/.ssh/id_rsa and ~/.ssh/id_rsa.pub with ssh-keygen and then copy ~/.ssh/id_rsa.pub to ~/.ssh/authorized_keys on the remote computer that you want to log into. You'll need to change REMOTE_USERNAME and REMOTE_HOSTNAME for the username and hostname of the remote computer and you'll also need to enter your password for the ssh-copy-id command to succeed:

ssh-keygen &&
ssh-copy-id -i ~/.ssh/id_rsa.pub REMOTE_USERNAME@REMOTE_HOSTNAME