Joomla. Where to find the html of the main page?

Question

CMS

Website: del
We need to make changes to the code of the main page.
The question is simple: where to find this file? Joomla 2.5
I read online about components, modules and more about this and that. I searched in the com_content component and did not find it in other places.
I would like a specific answer where to dig this file. Recently I asked the same question about Bitrix , now this problem again. It's kind of complicated.

Answer 1

If you need the main page code, then this is the template/yourtemplate/index.php folder

Answer 2

materials, material manager, then selected material. Joomla version 3.3.6.

Answer 3

in template