The correct format is exFAT. You will need OS version 10.2.1.3175 and above to use exFAT.
Supported MicroSD media card storage sizes for use with BlackBerry smartphones
FAT32 will work but with the limitations of FAT32.
See
https://en.m.wikipedia.org/wiki/ExFAT That will answer your questions about exFAT. If you are stuck using FAT32 then look up FAT32.
A new card should already be formatted. When you insert the 64GB card in a device that supports exFAT you'll see an error momentarily and then a message that the device is downloading drivers. It all happens in a few seconds.
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