Yes, you can use your own music as a sonnerie telephone on your Android phone. All you have to do is transfer the music files to your phone and select them in the ringtone settings. Make sure the music files are in the format compatible with your phone (usually MP3).
When downloading free ringtones from third-party sites, make sure you choose reliable and reputable sites. Avoid downloading files from unverified sources to avoid risk of malware or corrupted files. It is better to give preference to free ringtone apps available on the Play Store for maximum security.
To remove or change a ringtone on your Android phone, go to your device's ringtone settings. There you can select the ringtone you want to change and choose a new ringtone from the available library or delete the ringtone completely.