How to create a bootable flash drive that will allow you to boot from any disk in the system?

Question

Boot disk

Let me explain the situation. There is a laptop. The laptop has a SATA port for the HDD. Windows is installed on this HDD. The laptop also has an m.2 SATA connector. I inserted an SSD into this slot, started installing a new operating system on it, also Windows. Everything went well, the system got up and worked until the reboot. At the time of loading, it turned out that in the BIOS there was no way to choose to boot from m.2 media. I turned on all possible boot methods, there is a network, there is eSATA, USB, UEFI ... But there is no boot from the SSD I need connected to m.2.
You can boot only by inserting a bootable USB flash drive with the Windows installer into the USB. We start reinstalling the system, it suggests formatting the disk, we crash the system by long pressing power, we start loading again from the flash drive, and the system on the SSD is somehow picked up and loaded after booting from the flash drive and starting the installation of the operation again.
In general, the question sounds like this, how and with what utilities to create a bootable USB flash drive from which you could boot, see all the disks in the laptop, select the desired disk and start the system from it.
PS It is very important to the main disk, this is the HDD, do not make any changes and do not overwrite the bootloader there. Thus, in a normal situation, the system will always start from the HDD, and if necessary, another system from the SSD could be started via a USB flash drive.
What do you suggest?

Answer 1

Usually in the BIOS there is still a choice of the priority of the hard drives separately. Most likely, like a USB-HDD, your SSD will be on that list.