Your Y7 Prime 2018 features a microSD memory card slot. If your personal computer is compatible with that type of card (Most laptops are so-equipped), you should be able to save a music file
The Huawei Y7 Prime (2018) is an Android phone and there are plenty of free ringtone apps such as MP3 Cutter, RingDroid (open source) and more.
The Huawei Y7 Prime (2018) is Bluetooth-enabled. Bluetooth is a wireless system which lets you connect your cell phone to computers, headsets, car kits, etc. If your computer is also Bluetooth-enabled, simply establish a connection between both devices and transfer your music files from your computer to your Huawei Y7 Prime (2018).
Here are some of the free ringtones (Huawei Y7 Prime (2018)-compatible) offered here at MartinsRingtones.com:
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