Hello,
Thanks for the screenshots!
What I see on your screenshot is that the Taxonomy “Gender” has been assigned to the Post Type “Family Members”. There is no taxonomy assigned to a “Field Group”. Remember, a Field Group is a set of fields defined by ACF. On your screenshots, there are none.
If you want to let users select a “Gender” on your ACF Extended front-end form when creating a post, then you’ll have to add an ACF Taxonomy field (see documentation) or an ACFE Taxonomy Terms Field (see documentation) to the Field Group that is used in your Form. Then, you have to select that “Taxonomy field” in the “Post Action > Save > Post Terms” setting in the Form UI.
This is the same logic as the “Post Title” or the “Post Content” which are native WP fields. They have to be created manually in your Field Group (with a Text and Textarea for example), and then assigned in your “Post Action > Save > Title” & “Post Action > Save > Content”.
Hope it helps!
Have a nice day!
Regards.