You can try this tool to create a DVD or bootable USB drive to install the 64 bit version of windows 10.https://www.microsoft.com/en-us/software-download/windows10
When you made a bootable USB installer or downloaded the ISO did you chose the option to only download the x64 version and not pick the option to download both?
Also, what exactly makes you believe you have the 32 bit version installed? Being that the 32 and 64 bit versions are not compatible with each other I find it very interesting how a 32bit version could be used to upgrade a 64 bit version without it being a total wipe and clean installation.
Please right click on the start menu then click system and tell me exactly what it says for "System type:"
When you use the MediaCreationTool you need to select "Create installation media for another PC" NOT "Upgrade this PC now" then on the next screen UNCHECK "Use thew recomended options for this PC" then leave Edition as Windows 10 but for architecture select 64 bit NOT both.
So system info does state "64-bit operating system" ?
Ok, then do what I said to create 64 bit only installation media
You should be able to do a clean install with the 64bit only installation media, I do not believe it will allow you to "upgrade" 32 to 64 so you will have to move your files over manually and reinstall all of your programs.
No there should be no need for that. I have installed Windows 10 from DVD made from ISO clean on a new blank hard drive and it activated automatically, did not need to buy a license.Were you using the USB option? I would use the ISO download option and create a 64 bit only Windows 10 DVD installation disc.
Personally I'd use Windows 7 Pro for business use. I personally have no plans to use Windows 10 as my main OS, once Windows 7 support ends I'll use Windows 8.1 for a while, then when 8.1 support ends I'll be buying a Mac. lol.PS. I would backup your important files to a separate drive before doing the clean install off the DVD.
So did my method fix your problem? Please accept my answer and rate if it did as I do not get paid unless you do. Thank you.