The MagicBox (based on A1200) came with High Density Floppy drive and should be able to read PC disks. I'm not sure if the driver for PC disks is loaded and it needs to be verified.
To verify, you could start the MB by holding both mouse buttons during bootup. In the early start menu, choose boot without startup-sequence.
Then in CLI, type LOADWB
there maybe some errors during boot, just ignore.
When the WB is loaded, go to DEVS/DosDrivers folder and see if there is an Icon for PC0:
If is there, then it should work
If is not there, go see if you have STORAGE folder somewhere on the HD.
IF you do, go to DosDrivers folder and drag the icon to System: DEVS/DosDrivers folder and it should work after reboot.