Sure, you can certainly save your patches on the internal floppy. I wasn't sure whether the N364 had a floppy drive. That is certainly easier. But make sure you do save your patches and any other important data before loading up new sounds.

At some point though get a sysex receive/transmit utility for your computer and keep a backup of the N364 on your hard drive because even floppies end up failing after a long time or can be damaged. Your N364 manual will tell you how to do a bulk dump of the entire synth over sysex to a computer. It's just nice to have a backup.