Hi,

Perform a hard shutdown two times during the Windows boot screen. On the third time, Windows should boot to the recovery environment.

If you can see Windows Recovery, go to Step 2.

If you get a screen that says you need to use Recovery tools, you need another computer to create a recovery/installation media. You may also need Installation media if the Windows Recovery environment says your password is incorrect.

How to Create Bootable USB Flash Drive to Install Windows 10
https://www.tenforums.com/tutorials/2376-create-bootable-usb-flash-drive-install-windows-10-a.html

Boot from the USB Flash drive-Make sure you have disabled Secure boot/Fast boot in BIOS Settings and changed the boot order if required.

Disable Fast Boot in UEFI Firmware settings
https://www.tenforums.com/tutorials/21284-enable-disable-fast-boot-uefi-firmware-settings-windows.html

When you have successfully booted from the Installation media, click Repair your computer at the first screen after choosing the keyboard layout.


Step 2:

1. Use Startup repair: The first option you can try is to use Startup repair, which automatically detects and fixes problems. Depending on the severity of the problem, it may or may not be successful.

2. Uninstall Updates

The second step you can try is to uninstall the latest updates if Windows 10 fails to start after installing updates.

Choose Uninstall Updates.

Uninstall the update based on what was installed – a feature update or a quality update. Usually, the former is responsible.

3. CHKDSK:

If uninstalling did not help and is unrelated, the next step is to try using a Disk Check.

Choose Command Prompt in the list of troubleshooting.

Get the Current Windows Installation drive letter, which is either C, D, or E; Type BCDEDIT, and Press Enter. Note the letter.

Enter the command given below:
chkdsk X: /f /r (Replace X with the Current Windows Install Letter)

When done, you would see the output and restart the PC to check.

4. Another try you can give to fix is SFC SCANNOW through the Offboot switch. For this, follow the steps below:

First, find the Windows Install drive letter using the BCDEDIT command.

Then, try entering the following command:
sfc /scannow /offbootdir=C:\ /offwindir=C:\Windows

After the scan completes, you will see the results.
You can also try using DISM: dism /image:C:\ /cleanup-image /revertpendingactions


5. Reset this PC or clean install.

The last Step is a Reset. The catch with Reset is all applications would be removed, and files would be kept(you would be presented with the option to erase everything). Also, for this step, A healthy Reset Image is required, which maybe would be affected by corruption. If you are using Installation media, you can do a clean install after rescuing your files.

Rescue Files when Windows won't start
https://answers.microsoft.com/en-us/windows/forum/windows_10-update/rescue-files-when-windows-wont-start/862c143f-9239-4e63-8968-635e8ba9efd6

The steps are in detail with pictures here:
https://www.yourwindowsguide.com/2020/08/fix-windows-fails-to-load-in-pc.html

Content on the above blog is written by a Windows MVP, so it is safe. However, do watch out for ads.