The Interruptions feature allows sound/vibration (for phone calls, messages, etc.) to be turned on or off as preferred.
Alarms are always considered priority interruptions.
From a Home screen, navigate: Apps > Settings > Sound & notification.
If Settings is unavailable, tap the Apps dropdown menu (located in the upper-left) then tap Alphabetical. If still unavailable, refer to Manage App Icons.
Tap When calls and notifications arrive then tap Only allow priority interruptions.
Tap an option (e.g., Indefinitely, For 8 hours, For 15 minutes, etc.) then tap OK.
From the Priority Interruptions section, tap any of the following to turn on or off :
Events and reminders
When Phone calls and/or Messages are enabled, tap Calls/messages from then select an option (e.g., Anyone, Favorites, Contacts only).
From the Downtime (Priority Interruptions Only) section:
Tap Days, select the preferred day(s) then tap Done.
Tap Start time, adjust the start time then tap OK.