Bought my XPS 13 a month ago, and accidently bought the Linux-version.
I have a Win 10 code laying around, and wondering if i can replace the operating-system?
Or is the computer "tuned" för Linux?
Most Dell systems sold with Linux are also sold with Windows. You should be able to use it with your retail license. Follow the instructions here to make a Bootable USB:
Windows FAQs and OEM Downloads