Changing boot sequence to usb stick so I can use recovery program

Could someone please walk me through the last steps in changing the bootsequence of a ASUS GL552 laptop.

I am replacing an M2 SSD (serving as a C Drive) and want to restore the mirror image from the old SSD drive

I would like to boot from a USB thumb drive that has a rescue program saved to it. I was able to get into the laptop's bios but cannot see any option to change the boot sequence. See the second image. What do i have to do to boot from the USB thumb drive?

See the following two screens of the bios boot tab selections.

See if you can boot to the USB flash drive using the applicable F key:

List of PC brands with their corresponding hot-keys

Its hard to say not having the bios but what type of disk is c ie gpt uefi. The problem may be secure boot which will stop it booting and also if its set to uefi your rescue disk must be uefi

I think the usb stick might be MBR formatted so you need to enable CSM mode in BIOS (and maybe disable SECURE MODE too).
For invoking Boot option popup you could try F8 or ESC key (I think it's F8 for ASUS).

Just to muddy things up a bit more, some systems disable some of the different options (such as boot from USB).
You'll have to check in the other BIOS/UEFI screens to see if that's the case here