Hello
If it is asking you for answers to the security questions, it means the account is not linked to your Microsoft account, but it is a local user.
In this case, you will need to answer the security questions or use a password recovery USB if you have made one prior to this on this computer.
Otherwise, there's no other way around this. You will need to clean install Windows in that case to start over. Any attempt to bypass security measures is considered a violation of the code of conduct by the moderators on this platform.
Try this: from the sign-in screen, you can usually hold Shift, click Power > Restart, then choose Troubleshoot > Reset this PC > Remove everything.
If that doesn't work, do clean install.
The following steps should be done on a working Windows computer:
Download the Windows Media Creation Tool from Microsoft's official website. https://www.microsoft.com/software-download/windows10
Run the tool and select "Create installation media for another PC."
Choose your language, edition, and architecture (32 or 64-bit) and select "Next."
Choose "USB flash drive" as the media to use for the installation and select "Next."
Connect a USB flash drive with at least 8 GB of free space to your computer.
Select the USB flash drive you want to use, and then select "Next."
The tool will then download the required files and create the installation media.
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Now these steps will be done on your problematic computer:
Go to the computer's BIOS boot menu to have it boot from the USB drive.
Follow the on-screen instructions to install Windows 10, making sure to choose "Custom install" and select the option to delete all existing partitions.
Once the installation is complete, you'll have a clean installation of Windows 10 on your computer.