What to do when a heart stops, or a throat blocks

This explains what CPR and choking help are, and how they work. It is not a course, and reading it does not certify you. A hands-on class with a dummy is worth far more than any page.

If someone is in danger right now, stop reading. Call your local emergency number. Put the phone on speaker.

The steps here follow guidance that is shared across most countries. The emergency number is not. Ours says "your emergency number" for that reason. Look yours up now, before you need it.