Encender y usar un ordenador de escritorio sin Microsoft

Hello,

I’m not sure I’m posting in the right forum.

I have a slim desktop PC. I’m on Windows 10.

When I turn on my computer, it automatically logs into my Microsoft account. Unfortunately, the password via the mobile phone number doesn’t work at all. I never receive text messages. Only the local password works. This is not the password for my Microsoft account.

That is to say, I can only access my folders and files if my computer is connected to the Livebox via Ethernet cable. My PC does not connect via the wifi code.

I would like to access my computer’s folders and files without needing to connect to Microsoft. How to remove the Microsoft side while keeping Livebox internet?

I’ve read several things about this, but I’m a bit afraid to experiment with methods because I’ve read several scary news items such as if I unplug the Ethernet cable, my PC will never turn on again or my folders or files will be inaccessible when I try to connect with Microsoft with internet.

For members registered in these forums, how did you manage to boot the desktop and recover all your work, the folders and files on the computer without needing Microsoft?