Before diving into the "where" and "how," let's look at the "why." Updating your firmware is not just about new features. It is about security and stability.
Yes, free firmware exists, but you need to verify the SHA/MD5 checksum before flashing. Never pay for firmware. If a website asks for a credit card for "DG8245V10 firmware," close the tab immediately. huawei dg8245v10 firmware free