64 Bit Office

Office 32 bit is limited to using a maximum of 2GB of RAM which is shared between workbooks and add-ins.
Office 64 bit is only limited by available memory and system resources.

link - docs.microsoft.com/en-us/office/troubleshoot/excel/memory-usage-32-bit-edition-of-excel
link - support.microsoft.com/en-us/office/choose-between-the-64-bit-or-32-bit-version-of-office-2dee7807-8f95-4d0c-b5fe-6c6f49b8d261
link - docs.microsoft.com/en-us/previous-versions/office/office-2013-resource-kit/ee681792(v=office.15)

Cores and Logical Processors

Physical cores are number of physical cores, actual hardware components.
Logical cores are the number of physical cores times the number of threads that can run on each core through the use of hyperthreading. for example, my 4-core processor runs two threads per core, so I have 8 logical processors.