So how would I get Windows onto the USB drive. Also, is it free?
Free, portable, easy and fast and bootable USB drive.
For my use, I first made a ISO image of the windows OS Disk.
If you buy Windows directly from Microsoft, they'll offer to send you the retail box or give you the download. If you select the download, at the end they'll offer to install it onto media to make it bootable. You select the USB you want to make bootable and it does the rest.
If you're talking about putting it onto a USB drive because your new computer doesn't have an ODD, you'll need another computer with an ODD and you'll need to go through some other steps. I think Rufus can do it from what I remember.
Anyways, no, Windows is not free but putting your copy/license onto media to boot from it is.