How to let important people get through iOS 15’s Do Not Disturb or Focus settings

iOS 15 expands the options for providing exceptions to your sleep and focused work schedules.

The Do Not Disturb option added to iOS, iPadOS, and eventually macOS should be entered in history books for their contributions to people's uninterrupted periods of sleep and focused times while working. However, what if want to provide an exception for people important in your life, particularly for emergencies?