Here are some Apple resources you may find helpful (two support pages with the same title!):
Share your location in Find My on iPhone - Apple Support
Share your location in Find My on iPhone - Apple Support
Set up location sharing
1. Go to the Find My app on your iPhone.
2. Tap Me at the bottom of the screen, then turn on Share My Location.
3. The device sharing your location appears next to From.
If your iPhone isn’t currently sharing your location, you can tap Use This iPhone as My Location.
Note: To share your location from another device, open Find My on the device and change your location to that device. If you share your location from an iPhone that’s paired with Apple Watch (GPS + Cellular models), your location is shared from your Apple Watch when you’re out of range of your iPhone and Apple Watch is on your wrist.
You can also change your location sharing settings in Settings > [your name] > Find My.