With the newer cameras and doorbells that work ONLY in the Google Home app, you have to share access to all of your Google Nest devices:
With the older Google Nest cameras and doorbells that work in the Google Nest app, you can share a public or private link to your camera's live stream:
@Alde8araN thanks for posting here in the community and I understand your concern about sharing your Nest camera with your family member. To confirm, have you tried the steps from the link that MplsCustomer provided? Also, before you finish sharing the access, the Google Home app or Nest App will ask you about the type of access you wanted to give to your family member.
Looking forward to your response.
I appreciate the help, @MplsCustomer.