It's a good os however runs slower than windows 10 on my low-end computer. How do I change the os back to Windows? I have a USB stick and it isn't being read on elementary (it is working properly on my laptop)thanks in advance.
There is currently no way to do a change back/rollback to Windows XP, or any previous Operating System that you had before the install.
If you have a Windows (XP, or any other version of Windows) installation disk, then you could use it to install Windows on your computer. As far as drivers go, I wish you good luck.
A better option, is that you have a backup of your previous system. (This includes the entire disk.) Then you could restore the previous system from the back up.
Wish you good luck.