Angels have the Phone Box
When you boot your system to Kyhi's rescue media, you have a little, mini, "live" Windows operating system there to work with. It has some tools/programs on the desktop. But, you can just open File Explorer and use that to transfer your files from one place to another.
If you tell the computer to boot from USB or Optical drive, that is how you boot to Kyhi's rescue media. There are two ways to do this: One is to permanently change your boot order in your BIOS. The other way is to use the one-time-boot feature that most BIOSs have. I don't know your keys exactly, but I'll give you an example:
When first booting a system, very quickly you will see (usually in a bottom corner), something about pressing, say, F2 for boot options, or say, F9 to enter the BIOS. If you press the F2, it will give you the option to select your boot device only for that session. If you change the boot order in your BIOS and save it, that is permanent. Usually, if you set the order in the BIOS to be USB, then CD/DVD, then Windows Boot Manager (if UEFI), then the system will look for boot information in that order and use the first one it finds.
Hope that helps.