In https://learn.microsoft.com/en-us/xamarin/android/deploy-test/signing/keystore-signature?tabs=windows, it gives an example of the signature information:
Alias name: androiddebugkey
Creation date: Aug 19, 2014
Entry type: PrivateKeyEntry
Certificate chain length: 1
Certificate[1]:
Owner: CN=Android Debug, O=Android, C=US
Issuer: CN=Android Debug, O=Android, C=US
Serial number: 53f3b126
Valid from: Tue Aug 19 13:18:46 PDT 2014 until: Sun Nov 15 12:18:46 PST 2043
Certificate fingerprints:
MD5: 27:78:7C:31:64:C2:79:C6:ED:E5:80:51:33:9C:03:57
SHA1: 00:E5:8B:DA:29:49:9D:FC:1D:DA:E7:EE:EE:1A:8A:C7:85:E7:31:23
SHA256: 21:0D:73:90:1D:D6:3D:AB:4C:80:4E:C4:A9:CB:97:FF:34:DD:B4:42:FC:
08:13:E0:49:51:65:A6:7C:7C:90:45
Signature algorithm name: SHA1withRSA
Version: 3
Regarding "Owner: CN=Android Debug, O=Android, C=US", O may stand for organisation, and C may stand for country.
What does CN stand for?
"CN" stands for "Common Name".
See https://docs.oracle.com/cd/E24191_01/common/tutorials/authz_cert_attributes.html for the list of all attributes of the certificate.
In Android, the CN does not have any particular significance so you can put whatever string you want, but if that certificate is used for SSL, there are some requirements: https://www.ssl.com/faqs/common-name/