Once this is on, your eligible activities count in Harry's automatically. No screenshots or links.
Harry's reads runs, rides, swims, workouts and calories from Apple Health. Not every challenge uses this data; each challenge in the app shows what it tracks.
Open the Garmin Connect app on your phone, not on the watch.
Tap More in the bottom-right corner.
Scroll down and tap Settings, then Connected Apps. On older versions of the app this is labelled 3rd-Party Apps.
Select Apple Health and tap Connect with Apple Health.
On the permission screen, tap Turn On All. At a minimum, turn on Workouts, Distance and Heart Rate.
Done. The Apple Health screen now reads You're connected with Apple Health. After your next workout, open Garmin Connect once so it can pass the activity through.
Done? Back in Harry's, open Settings > Data & Syncing. The Last sync time updates within a few minutes of your next activity.