To add an emergency contact on an iPhone, use the Health app or the Settings app:
- Open the Health app, tap Browse (bottom right), then tap your Apple ID picture. Tap Medical ID and then Edit.
- Scroll down to Emergency Contacts, tap add emergency contact.
- Choose a contact from your Contacts list and specify their relationship to you.
- Repeat to add more contacts, then tap Done to save.
Alternatively, in Settings, go to Health > Medical ID > Edit > add emergency contact and follow the same steps. Your emergency contacts will be notified with your location if you use the Emergency SOS feature on your iPhone.