Securing VM in windows 10 (this is to get the domain and change the network to bridge)

1. What is the problem? Be very detailed.
Please, how can I secured the VM (Virtual machine)? I followed the documentation. Where I am getting the problem is changing the password on the VM to the secured one. That is, the password from aggregate to another one, maybe orbits148.

2. What app or server are you using and on what device and operating system? Include version numbers.
I am using Virtualbox and Virtual machine 6.0. I am using it on Windows 10
3. What you have you tried to fix the problem?
I have changed the aggregate password on http://localhost:10080, but I couldn't secure VM so I can get the domain
4. What steps can we take to reproduce the problem?
please how can I write/change the VM password for root login on the command line? The password is not changing.
5. Anything else we should know or have? If you have a test form or screenshots or logs, attach below.
I have followed the documentation on opendatakit, I didn't get it