I recently changed from Win7 to Win10 after reading somewhere that in January 2020 Microsoft will stop allowing Windows 7 uses to upgrade to 10. I put it off for years because I had my OS running since 2011 and I wasn't too keen on the changes and ads and Cortana and things.
I chose not to do the "Upgrade" path because of fears something would go wrong, so instead I spent an entire day sorting my data and backed everything up onto an external HDD, and then ran a clean USB install using my Win7 key to activate Win10. Everything went fine. Win10 takes a little getting used to with tweaking the layout, changing privacy settings, disabling Cortana and generally getting used to the changes etc. But ultimately I'm glad I did now, it's also nice having a fresh start from my old bogged down computer.