I already had a premium Spotify account upgraded it to family plan send the invites to my family who all live with me and we can't use the Spotify account at the same time.
@KevinCepeda Is right about the Premium for Family. Each member will need their own account and you have to send the invites. All the info about it is here.
Your family should use their own accounts. Go to your account web and click in the family plan and add one an one each of your family's members.