Change family sharing password

What happens when you try? Error message(s)? Have you checked Settings/Screen Time for any restrictions?

If you know the current password.

 Apple ID Password Change.   -   

https://youtu.be/LIOapHreNe4

 What to do after you change your Apple ID or password - Apple Support  -   I suggest doing this before you change your Apple ID or password.

If you forgot the Apple ID (iCloud) password, enter the Apple (iCloud) ID, and click Forgot Password on the sign in page. See if you can get a Rescue or Notification email option if necessary. Link to contact Apple Support at the end of the 2nd article.

Apple ID - Manage  -     

Apple ID – Forgot Password  *