The "Bootable" legacy ISO you've used is in fact not bootable, it relies on CDROM emulation provided by BIOS. VMs don't usually do this sort of emulation. If you set the guest OS to something like ...

The virtual machine may fail to boot from an ISO because the boot order prioritizes the virtual hard disk over the optical drive, resulting in a “No bootable medium ...

Universal USB Installer is a versatile ISO-to-USB tool that builds bootable Linux, Windows, and multiboot diagnostic flash drives with ease. The Universal USB Installer (UUI) is a powerful bootable ...

The Universal USB Installer (UUI) is a powerful bootable USB software tool for creating USB boot drives from ISO files, perfect for installing Linux or Windows, running live systems, or building ...