I would like to create a bootable USB drive or SD card on a public library computer (which will be inserted into a Raspberry Pi).
I assume the library computer would certainly allow me to download an operating system image, for example Ubuntu 21.04, and to copy that file to an insertable USB drive. However, I do not think I could reformat that drive as a bootable disk, because I would need an application to do so, and the public library computer would not permit me to install new software.
Is there any way around this? Is there some way I can download a bootable operating system and just copy it to the USB drive, so that I can do the rest of anything that needs to be done from my Raspberry Pi?