Your Moto E5 Plus has a microSD memory card slot. If your personal computer is compatible with that card type (Most laptops are so-equipped), you should be able to save a music file
The Motorola Moto E5 Plus is an Android phone and there are plenty of free ringtone apps such as MP3 Cutter, RingDroid (open source) and more.
More on free ringtones
Here are some of the 100% free ringtones (Motorola Moto E5 Plus-compatible) offered here at MartinsRingtones.com:
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