Hello the prestige, welcome to Seven Forums!
There is no upgrade path from 32-bit to 64-bit Windows, it will have to be a clean install
and the best way forward, after you have copied out
or made back-ups
of the data you need to save to external media, is to do a wipe secure erase
of the entire Hard Disk Drive and be sure to post back with any further questions you may have and to keep us informed.
You will have to reinstall all the programs/apps that you use as they integrate themselves into the Windows registry and are not moveable from one Windows installation to another so be sure to save the program installers and the product activation keys where applicable.