
You can copy many image files at a time and ventoy will give you a boot menu to select them. With ventoy, you don’t need to format the disk over and over, you just need to copy the image files to the USB drive and boot it. It's not limited to USB either it supports pretty much any kind of removable disk.Ventoy is an open source tool to create bootable USB drive for ISO/WIM/IMG/VHD(x)/EFI files. If you want persistent storage for a Linux live image, it can do that too.

You can have as many ISOs as the key will hold, and unlike a DIY solution with GRUB4DOS, there's no need to manually edit config files, add the ISO filename into a list or anything. It will boot Linux, BSD, Windows, or any standard ISO, whatever you want, and works on both BIOS and UEFI machines. You don't need a key-writing tool at all. It's quicker than writing a file, especially with Windows tools such as Rufus.

Just copy some ISO files into the big partition, shove the stick into any PC or Intel Mac, and boot from it. It partitions and formats your key with a small boot partition and a bigger empty one. Download either the Linux or Windows version, whichever's more convenient – it's only 18 meg, about a quarter of the size of BalenaEtcher, for instance – and run it.

All you need is a spare USB key with enough space for a few ISOs eight gigs will work and 16 is plenty. Ventoy makes this quicker and easier than anything else we've seen, though.
