How to use library and data binding

Hi, I’ve done a test because I want to understand how to use library (include and exec).
So, on this page
https://www.campaniaturismo.org/admin/admin-vicinanze-comuni-add-new.php?id=8
I want to show the name of a city filtered by a query string.
On this page you can see:
Aggiungi località nelle vicinanze di Avellino
Avellino is taken from a database filtered by the query string id=8
I’ve done it in the classical way, an action file with $_GET variable in the input section of the action file.
I try the same thing using library and an exec API.
Unfortunately it doesn’t run.
You should see “Avellino” under the previous row but you don’t.
Does anyone know what’s wrong?
Thank you

Schermata 2020-12-23 alle 16.00.583200×1800 1.1 MB

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