Absolutely yes!
When I was a Guide Leader (with my own Rainbow unit too) I taught girls appropriate first aid and emergency calls from the age of 5. How to make the call, what information the call handler might ask, even doing practice scenarios with my Leaders pretending to be the call handlers.
Little ones should also know their full name, address.
If I was still in GGUK I’d also teach the older girls (older Brownies and up) about WhatThreeWords too.
Appropriate to age first aid is also a good skill, adding
more knowledge as your child gets older and able to
do things like CPR (it takes a lot of oomph!), assessing for injuries (teens), specialist knowledge on things like hypothermia for older teens that may be more adventurous and go out and about.
I had one Brownie (nearly 8) who was given a bravery award at school for helping her friend who’d fractured their arm when they were at the park
and friends fell, getting help from another adult present who called 999, reassuring her friend, making sure she didn’t move until help was there, giving the ambo crew on scene help with address to find friend’s parents, she was calm throughout, and an absolute star!
St John’s Ambulance have a variety of resources and training, starting from 5 years old with Badgers.
Parents should learn basic first aid too (so many easy to follow tutorials on YouTube from the St John Ambulance channel). That includes treating minor illnesses, knowing the signs when to get help and when it’s safe to treat at home.
Lead by example!
I taught DD and DS basic first aid as kids, now both adults, DD works in the NHS on the frontline, DS’s MIL is a paramedic and ensures he keeps his knowledge up to date lol!
I can only speak for Apple products, but you can dial 999 from a mobile phone; if the screen is locked, tap ‘Emergency’ and then 999 as usual.
I also taught both kids water safety, vital especially with teens and this hot weather.