1. there isn’t any way to alter the field group order on the user profile page. If you have more than one field group on the profile page you can order them but they will all appear below the standard user profile fields.
2. I did some testing. It appears that bbpress uses the standard user profile form and there’s no real way for ACF to know the difference. I’m also assuming you mean the edit profile page that appears on the front end of the site. What you need to do is add a new location rule to stop the displaying of a field group on the front end of the site. Add this code to your functions.php file