A few commands to try if windows is not booting properly or stuck in a windows update reboot loop
bcdedit /set {default} recoveryenabled No - Turn off Automatic Startup repair (change to yes to re-enable)
bcdedit /set {bootmgr} displaybootmenu yes - Turn on F8 recovery options menu (no to turn off again)
Rebuild the BCD
bcdedit /createstore %temp%\emptyBCD
bcdedit /import %temp%\emptyBCD /clean
bcdboot C:\Windows
Revert windows updates
dism.exe /image:C:\ /cleanup-image /revertpendingactions C: may differ depending on where the windows install is located
Some files that can be deleted to help reset windows update chain
del D:\Windows\SoftwareDistribution
del D:\Windows\WinSxS\cleanup.xml
del D:\Windows\WinSxS\pending.xml