Sounds like the first upgrade to Windows 10 was bad. yes you can install the 10 64bit program on your computer. You will have to download a clean install of windows by going to the Microsoft website to do that. You can go here: https://www.microsoft.com/en-us/software-download/windows10/ and download the tool and then choose 64 bit and then download a clean install of Windows 10 64 bit.
Ok no problem. Keep me posted.