Does the factory reset reset the configuration file (hw_tree.xml) as well on HG8245H?

Good day, everyone!

This post enquires whether the factory reset resets the configuration file (hw_tree.xml) as well on HG8245H. Please see more details below.

ISSUE DESCRIPTION

So, I have an HG8245H and I wanted to change the superuser password as everybody with Google could search the telecomadmin password. I don't want any outsider accessing my router. 

I followed a tutorial on YouTube on how to change it via the config file, and here's where I messed up.They said that in the config, it was encrypted in SHA256 and the****5. After I encrypt the password I desired, I change the config and upload it. Turns out, it wasn't encrypted like that. So I was locked out from the superuser as well. Can only use the root admin access, so with limited access. 

So, my question is: if i reset my router, will it reset back to the original config file? As I'm the owner of the WiFi, I wanted to have full control over my network. I don't want outsiders to download a huge file and to mess with my personal use WiFi speed. And now that I've researched it, turns out HG8245H doesn't have a bandwidth control/QoS either.

Is there any way to set up a guest network with limited bandwidth? Please assist me with regards to whether the factory reset resets the configuration file (hw_tree.xml) as well on HG8245H. Thanks!