Wikipedia redirects "Windows Boot Manager" to the Windows Vista Startup Process. To avoid a problem dual booting Windows 10 with Linux, I would want to note the UEFI and GPT configuration from a live Linux flash drive. I'm not sure what the Windows equivalent to GRUB 2 would be, but I would want to save those settings as well as the partition table.
How do I get that diagnostic data before proceeding with any Linux install steps?