Red flashing lights

You can't fix your computer issue with the phone. Also rooting is for your phone not your computer.

Start at the beginning with some details, need to know brand and model of computer, what is the exact error message? Does the system try to load Windows then fail or this happen before Windows starts? Did anything else happen before the issue started? You will probably need to make a Windows boot media and run a repair setup or a full setup of Windows. Maybe need a new hard drive for the system.