The Galaxy Note9 sports a microSD memory card reader. If your laptop or personal computer can also read that card format (Most notebooks are so-equipped), you should be able to transfer music files
The Samsung Galaxy Note9 is an Android smartphone and the Android market offers a bunch of free ringtone apps such as MP3 Ringtone Maker, Zedge and more.
Here are links to some of the free ringtones (compatible with your Samsung Galaxy Note9) we offer:
Free Horror Ringtones Free Tropical Ringtones Free Ringtones-a-gogo Free Techno Ringtones Hear All Our Free Polyphonic Ringtones