To upgrade Windows 10 to 64-bit, you'll have to perform a clean install, so back up all your data; ensure you have a 64-bit CPU. Download the Windows Media Creation Tool to create a 64-bit Win 10 ...

It will be the 64-bit version for most people, but you can confirm if you are 32-bit, 64-bit, or running ARM using these instructions.

Windows 10 is finally getting a 64-bit version of Microsoft's OneDrive syncing app But it warns Surface Pro X users with an Arm processor to stick with the 32-bit version of OneDrive.