Firstly, you need to find your Canonical ID. (https://www.teachonetofish.net/aws-iam-cli/)

The canonical user ID is the Amazon S3–only concept. It is a 64-character obfuscated version of the account ID. Therefore you can’t get anything out of the canonical user ID because it’s almost certainly a one-way hash.

aws s3api list-buckets --query Owner.ID --output text

b3dd23678902c3789775cd1371268365

Then, you can find the bucket ID to see if it matches your ID.

aws s3api get-bucket-acl --bucket bucket-name --output json

{
    "Owner": {
        "ID": "b3dd23fdfeb2c3789775cd1371268365"
    },
    "Grants": [
        {
            "Grantee": {
                "ID": "b3dd23fdfeb2c3789775cd1371268365",
                "Type": "CanonicalUser"
            },
            "Permission": "FULL_CONTROL"
        }
    ]
}