add dynamic widgets on tap and save values flutter - flutter

Question

I'm trying to add a new row of widgets (select gender and age from a drop-down menu ) when a user taps on adding a child and saves different data from each row also when deleting a child by index it should not affect the other values the user entered how can I achieve that?
this is the UI
UI
and here's the code
class ChildrenSection extends StatefulWidget {
const ChildrenSection({
Key? key,
}) : super(key: key);
#override
State<ChildrenSection> createState() => _ChildrenSectionState();
}
class _ChildrenSectionState extends State<ChildrenSection> {
int _count = 1;
List<String>? onGenderSelected;
#override
Widget build(BuildContext context) {
onGenderSelected = List<String>.filled(_count, '', growable: true);
return Row(
children: [
Text(
'Children',
style: NannyFinderTheme.createAdTextStyle,
),
SizedBox(
width: 10.w,
),
Expanded(
child: Column(
children: [
SizedBox(
height: (50 * _count).toDouble(),
child: ListView.builder(
itemCount: onGenderSelected?.length,
itemBuilder: (context, index) {
return _addChild(index);
}),
),
SizedBox(
height: 10.h,
),
InkWell(
onTap: () {
setState(() {
_count++;
});
},
child: Row(
children: [
const Icon(CupertinoIcons.person_badge_plus_fill),
SizedBox(
width: 10.w,
),
const Text(
'Add a child',
style: TextStyle(decoration: TextDecoration.underline),
)
],
),
)
],
),
),
],
);
}
Widget _addChild(int index) {
return Row(
children: [
InkWell(
onTap: () {
if (index != 0) {
setState(() {
_count--;
});
}
},
child: Icon(index == 0
? CupertinoIcons.person_fill
: CupertinoIcons.person_badge_minus_fill)),
SizedBox(
width: 10.w,
),
_children('Girl', index),
SizedBox(
width: 4.w,
),
_children('Boy', index),
//const Spacer(),
SizedBox(
width: 10.w,
),
Expanded(
child: CustomDropDownButton(
value: kListOfChildrenAge.first,
menuList: kListOfChildrenAge,
onChanged: (String? value) {},
),
)
],
);
}
Widget _children(String text, int index) {
return InkWell(
onTap: () {
setState(() {
onGenderSelected?[index] = text;
});
},
child: Container(
height: 30,
padding: EdgeInsets.symmetric(horizontal: 8.w),
decoration: BoxDecoration(
color: onGenderSelected?[index] == text
? NannyFinderTheme.ligtherPrimaryColor
: Colors.white,
borderRadius: BorderRadius.circular(4.r),
border: Border.all(width: 0.5, color: NannyFinderTheme.grayColor)),
child: Center(
child: Text(
text,
style: TextStyle(
color: onGenderSelected?[index] == text
? Colors.white
: Colors.black,
fontWeight: FontWeight.bold),
)),
),
);
}
}