It was possible to format 720k floppies on a PC and use them on the ST, if that was the case then if you have a DOS PC or any version of Windows prior to Windows Vista you can just read the files directly.
If the floppies you have were originally formatted on the ST, then you’re going to have to do what Jarno suggests above. N.B. it must be an original internal floppy (with the flat cable), a USB drive will not work, nor will most laptop drives (which are internally USB).