Let's create a Byron address:
$ cardano-cli byron key keygen --secret test.skey
$ cardano-cli byron key signing-key-public --secret test.skey
public key hash: 7e5078fa6e2a8308
public key (base64): RNbpyp7dquTkVJJ5hXxs4hLjtVCynfQvuVTi5gicU55McTshDzVSGQdNfJHN995WVWsPYpaAyIQ8omBBR8uagA==
public key (hex): 44d6e9ca9eddaae4e4549279857c6ce212e3b550b29df42fb954e2e6089c539e4c713b210f355219074d7c91cdf7de56556b0f629680c8843ca2604147cb9a80
$ cardano-cli byron key signing-key-address --mainnet --secret test.skey
Ae2tdPwUPEZHvh7P2QsxENNDeHZ9K4vw4Pfk3LY9gxkrAVVLSTmXaCvxxFf