If are able to connect both phones to a PC via a suitable USB cable, then one method is to initially connect and copy the music from the iPhone to PC Disk. Then, connect the Samsung to the PC and copy the music files from PC to Samsung device.
Info on how to perform File copy to/from PC should be in the phone manual which is available from the Phone manufacturers support web site.
As an alternative to connecting to PC, you may also be able to transfer direct via Bluetooth if both phones support this feature. Again info will be available in the phone manuals.