Both you and your relatives will see basic profile information: the first and last names listed in your profile, sex at birth, date of birth, country, and estimated relationship. If you add a profile picture, they will also be able to see it.
You can change your username and profile picture under Settings → Profile. Images containing violence, sexually explicit content, nudity, or offensive material are not allowed.
At present, it is not possible to hide specific profile fields. If you do not want to share this information, do not activate DNA Connect or deactivate it.