Make bootable uefi iso

I have a bootable usb drive that could be auto boot and run script.

I tried many tool (ex: ImgBurn, WinISO...etc) to change the usb to a bootable iso file.

But I still cant not see it appears in the bios setup menu.

But I could see "UEFI: usbname" option like below pitcure when using usb drive.

My usb architecture

USB
     -- STARTUP.nsh
     -- EFI
         -- BOOT
             --BootX64.efi

Are there other paramters or files I losed when transfer to a bootable iso.

I found a solution.

1. make a img(ima) included these files.
2. Set the img as a blank iso's boot image and save.

It could work.