I have a Lenovo Thinkpad that was running Mint Linux using full-disk encryption. I downloaded the Windows 10 ISO from Microsoft and used whatever Mint uses to create bootable USB devices to put the Windows 10 ISO on a Seagate Backup Plus Slim. I tried to boot from USB using the Lenovo boot menu but the computer went to the same Mint disk encryption log-in screen as usual. Inside Mint, I deleted the partitions on the hard drive and rebooted. Now when I boot it goes to the Grub rescue command prompt.
I'm guessing that either the tool I used in Mint to create a bootable USB device didn't do the trick. Or maybe the Windows 10 ISO isn't bootable unless you use Microsoft's media creation tool itself?? If that's the case, then how can I make a bootable Windows 10 USB device without using Windows in the first place?? :-)