The share location with watch faces is greyed out, so I can’t change it.

Hello MellG,

Welcome to Apple Support Communities!

We want to help you check the Restrictions on your device.

You can use the steps here to verify your settings on your iPhone:

"Set Content & Privacy Restrictions

1. Go to Settings and tap Screen Time.
2. Tap Turn on Screen Time, then tap it again. Choose "This is My [Device]" or "This is My Child's [Device]."

• If you're the parent or guardian of your device and want to prevent another family member from changing your settings, tap Use Screen Time Passcode to create a passcode, then re-enter the passcode to confirm. After you confirm your passcode you'll be asked to enter your Apple ID and password. This can be used to reset your Screen Time passcode if you forget it. 
• If you're setting up Screen Time on your child's device, follow the prompts until you get to Screen Time Passcode and enter a passcode. Re-enter the passcode to confirm. After you confirm your passcode you'll be asked to enter your Apple ID and password. This can be used to reset your Screen Time passcode if you forget it. 

3. Tap Content & Privacy Restrictions. If asked, enter your passcode, then turn on Content & Privacy Restrictions."

This Apple Support page has the full details: Use parental controls on your child's iPhone, iPad, and iPod touch - Apple Support

Or if you're wanting to share and view your friend's location, use these steps:

"Add a friend

1. Open the Find People app  on your Apple Watch.
2. Scroll down, then tap Share My Location.
3. Tap the Dictation, Contacts, or Keypad button to choose a friend.
4. Select an email address or phone number.
5. Choose how long to share your location—for one hour, until the end of the day, or indefinitely.

Your friend receives a notification that you’ve shared your location. They can choose to also share their location with you. After your friend agrees to share their location, you can see where they are in a list or on a map in the Find My app on iPhone, iPad, iPod touch, and Mac, or the Find People app on Apple Watch.

To stop sharing your location with a friend, tap your friend’s name on the Find People screen, then tap Stop Sharing.

To stop sharing your location with everyone, open the Settings app  on your Apple Watch, go to Privacy & Security > Location Services, then turn off Share My Location."

Detailed here: View a friend’s location with Apple Watch - Apple Support

We hope this helps clear up the question about your Restrictions settings so you can share location with your Apple Watch.

Cheers!

Hey MellG,

We'd like to ask some questions that may help you get more answers.

• Which iPhone do you have and the software version installed?
• Which watchOS version is on the Apple Watch?
• Could you provide more details about the setting that was changed?

Take care.