How to install directly windows to usb drive, I mean you will install windows on a usb drive then you set boot device to usb drive on computer then it will boot to windows 7/8/10? Is it possible? I did not mean install windows on computer from usb.
I do not think it will work. You can try using a live Ubuntu drive if you're trying to recover files from a corrupted Windows installation. Or you could use your Windows installation media to try and repair it.
It can be done. Search for WinToUsb. Download that, follow the steps. Not sure why you want this though. Accessing Windows from a USB drive will be pretty slow.