Hey there, Kevin!
Unfortunately you cannot upgrade your OS from a 32-bit to 64-bit. You have to fresh install the 64-bit version and delete your 32-bit one.
Or you can install it as a second operating system, but you'd have to re-install everything that was on the 32-bit and re-configure it for 64-bit version of the OS. You should probably contact the OS tech support for assistance with this.
Hope I helped though.
SuperSoph_WD