Floppies

The floppy drive is where you can insert a square 3-1/2” hard diskette.
The old 5-1/4” flexible diskettes are nearly extinct.

Unlike all the other parts of your computer on this page, floppy drives are pretty standard.  Any floppy you buy should work in your computer.  As far as which floppy drive is best, all I can say is "You get what you pay for!".