How can I setup two iCloud Keychains?
There's no way to have more than a single iCloud Keychain I'm afraid. Other Keychains you create locally on your Mac are only for use on that Mac.

Until Apple allows Keychain Management on iOS from Settings you're out of luck. If you're interested to know how iCloud Keychain works, see here: https://support.apple.com/en-au/HT204085