The Power 2 has a microSD memory card reader. If your personal computer can also read that card type (Most notebooks are so-equipped), you should be able to save music files
The Power 2 is a smartphone. Most smartphones will let you save any mp3 song available online by touching and holding your finger on it, then selecting 'save.' Once a music file is stored on your library, tap-and-hold it and select 'assign' in the contextual menu.
The Ulefone Power 2 is an Android phone and there are plenty of free ringtone apps such as MP3 Cutter, Zedge and more.
More on free ringtones
Here are links to some of the 100% free ringtones (Ulefone Power 2-compatible) offered here at MartinsRingtones.com:
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