To change the notification sound on your iPhone, go to Settings > Sounds & Haptics. You can change the notification sounds on this page for the Text Tone, New Voicemail, Calendar Alerts, Reminder ...
To change your Samsung phone's notification sound, go to "Sounds and vibration" in the Settings app. You can import audio by downloading sounds to your phone and ...
You can change notification sounds for emails and calendar events directly within the new Outlook app for Windows. In classic Outlook, you can choose whether to play a sound when a new email arrives.