Elaine is correct. It would be better to do a clean install of the new OS.
Even though MS also makes Windows upgrades, it strongly advises customers to do clean installs if possible to have a known working state of the new OS and also to avoid migrating problems that may have already existed in the old OS into the new OS.
What kinds of conflicts? Device conficts, software conflicts... Can't tell them all before they happen but when they happen, it's really what we call "pain in the a*$"!
Thanks for the reinforcement, Van. Whatever conflicts may occur they are just a pain in the arse and should be avoided if at all necessary. That is why we recommended a clean install in the first place.