How can I get the submitted information

Answer 1

With the help of javascript
You can use getElementById()
You can read more about this on the Internet.

Answer 2

It is not possible to retrieve submitted information from visitors using front-end JavaScript alone.

Front-end JavaScript is executed on the client-side (in the user's web browser), and therefore does not have access to the server-side resources and data. In order to retrieve submitted information, a server-side language such as PHP or a serverless backend such as a cloud function would be required to handle the submission and retrieve the data from a database or other server-side resource.