Multiple OPERATING SYSTEM FROM EXTERNAL HDD?

If you mean a way of not having to use individual CDs for installing an operating system, the answer is yes. First you have to make the external hard drive bootable as a CD drive (the Boot image would have to be one for a CD and not a hard drive) , then you would create individual folders for each operating system. Once this is done you would copy the contents of the CD to that directory. The computer you would work with must be able to boot from USB. Then you would open the dierctory for the Windows you want to install and type in the command setup. This should start the Windows installation process.