You are doing it wrong, as APEX is perfectly capable of inserting row(s) based on a HTML form submit.
As to what is wrong - not much to say given the complete lack of details you provided...
Seems to me (in your example) you're trying to add a child record but you're missing the parent record.
Have you tried inserting any values in the top section? (Parent section).
I enetered few parent records also for few fields that is not shown on screenshot and not given any releationship .
both regions coloumn on same tables
Please help me