Many of those drive less models put off you buying the external drive. I see Walmart has USB DVDRW drives for about 25 bucks so that's where many get those if they need a drive. The big upside to this is that it can be used on many computers.
Windows 10 on USB can be downloaded from the web but the instructions change over time. Use this phrase to find current instructions.
"How do I create a Windows 10 installation USB stick?"
Hi , can ne1 tell me where to get Windows on a usb? My wife's laptop got stepped on by our kiddies and the hard drive was knackard so I got a new one a bit better than the one that was in it before but now I need to add new software to it I don't really know where to start but I want to try and (DIM)
it has no CD/DVD drive only usb ports so I wanted to get Windows 10 on a usb or something like! Is this right? Can I get it? and am I doing the right things? Lol

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