I created a simple bootloader in assembly and I compiled it with nasm:
nasm -f bin bootloader.asm -o bootloader.bin
I used qemu to emulate the "os":
qemu-system-x86_64 bootloader.bin
This command works because it opens up qemu and runs the bootloader (the goal is writing "Hello World" to the screen).
I also converted it to a .img file (I renamed the .bin file) and I loaded it in VirtualBox with a virtual floppy drive, and this also worked.
Now I would like to burn my bootloader onto an 8GB USB stick so I can run it on actual hardware.
I tried every program and every method to convert a .img to a .iso that I could open with Rufus and put it in my USB drive but when I plugged it in my other computer which I use for tests it just wrote "No bootable device -- insert boot disk and press any key".
I don't know what to try anymore and even searching on Google for information didn't help.
How can I make a bootable .iso from a RAW .bin file (no fancy stuff because my os is still in 16 bit real mode)?