Recommend good articles about MVC Opencart?

Question

PHP

What articles can you recommend in order to master MVC Opencart'a or MVC in general.
Specifically in my case, I would like to learn how to add variables to not only certain tpl template files.
(which are not declared in the required template - for example, $category is declared only for header.tpl , but I would like it to be used in home.tpl, etc.)
What literature to read?

Answer 1

About MVC Opencart'a official docks will be enough:
docs.opencart.com/developer/module
docs.opencart.com/developer/product-feed
docs.opencart.com/developer/loading
although everything is clear there.
Specifically, according to your desire, it is necessary to decide depending on the details.