To generate keys for SSH client:
ssh-keygen [-t rsa | rsa1 | dsa ] [-C <comment>] [-b bits]
For example:
ssh-keygen -t rsa -b 4096 - C [email protected]
Default location is ~/.ssh/id_rsa
for private and ~/.ssh/id_rsa.pub
for public key.
For more info, please visit man.openbsd.org