If you're looking for an in-depth paper on the HG8546M firmware, I can suggest some general topics that might be covered:
To obtain the official software, you generally need to log in to the Huawei Enterprise Support Portal with a registered account that has the necessary permissions. huawei echolife hg8546m firmware download link
You can often update the device without a manual file download: If you're looking for an in-depth paper on