: Type these commands in order, pressing Enter after each:
bootrec /fixmbr — Writes a new Windows-compatible MBR to the system partition.
: Insert your Windows installation USB/DVD and boot from it.
bootrec /fixboot — Writes a new boot sector to the partition.
bootrec /rebuildbcd — Scans for installations and rebuilds the Boot Configuration Data. How Do I Fix the Master Boot Record (MBR)?
This is the most direct method and doesn't require downloading extra software if you have a Windows installation or recovery USB.
: Select Repair your computer > Troubleshoot > Advanced options > Command Prompt .