How to make changes to the Joomla code?

Question

Joomla

Guys, a friend asked me to add an input to the son-matras.ru/otzyvy
page under the review on the right. I meet Joomla for the first time. How is the engine, I can not understand? I am looking for words from this page through a global search in the site folders, but they are not found .. I can’t even determine the module folder because of this .. Is the content stored in the database? Or somehow cached?
Tell me, please, in which direction to dig?
Thank you very much in advance

Answer 1

Is the content stored in the database?

Yes. And cached too.
The component is called RSForm, the module, respectively, is the same. Everything is added through the admin panel, there is no need to edit the code, go to Components > RSForm, look for the feedback form there, and add an additional text field through the administrative interface. Profit.