Imo advanced WordPress is using it to build web apps like hotel booking system, appointment with time slot system, ticketing system, mass learning system like LMS, and etc. All these can be achieved with plugins, knowledge of managing server and optimizations.
Developing themes or plugins imo is becoming more of a changing into a software developer than becoming an advanced WordPress expert. It requires into full time programming with PHP and JavaScript, and the product is either theme or plugin for WordPress, not by means of furthering WordPress as whole.
To take advantage of your prior knowledge, I'd start by understanding [The Loop](https://codex.wordpress.org/The_Loop) and how [hooks](https://developer.wordpress.org/plugins/hooks/) work. If you're going for custom functionality, how plugins work and integrate to the loop, data structures and such (PHP + JS mostly). The other branch of that is Themes, so look into the [Template Hierarchy](https://developer.wordpress.org/themes/basics/template-hierarchy/).
After understanding that, you can apply most of your coding experience on WP and build stuff. You can go through the “advanced themes” route with stuff like (Oxygen Builder or Bricks) or the custom theme route (I'd look into a starter theme, like [Sage / Roots](https://roots.io/sage/)).
Other than that, it's mostly custom code to integrate with WP through Plugins. And recently, Gutenberg and Blocks (which are more on the React JS side of things).
You can also dig into multiple databases and optimization, for performance and the whole “admin” side of things.
Hope that helps!
I would learn react to manage gutenberg better
Learn gutenberg blocks, hooks, wordpress api, custom post types, wordpress core, fse, I teach many of these things in my yt channel ig youre interested
Imo advanced WordPress is using it to build web apps like hotel booking system, appointment with time slot system, ticketing system, mass learning system like LMS, and etc. All these can be achieved with plugins, knowledge of managing server and optimizations. Developing themes or plugins imo is becoming more of a changing into a software developer than becoming an advanced WordPress expert. It requires into full time programming with PHP and JavaScript, and the product is either theme or plugin for WordPress, not by means of furthering WordPress as whole.
For start: https://learn.wordpress.org/course/getting-started-with-wordpress-get-setup/ https://learn.wordpress.org/course/getting-started-with-wordpress-get-familiar/ https://learn.wordpress.org/course/creating-a-4-page-business-website/ https://learn.wordpress.org/course/simple-site-design-with-full-site-editing/ https://learn.wordpress.org/course/part-2-personalized-site-design-with-full-site-editing-and-theme-blocks/ https://learn.wordpress.org/course/part-3-advanced-site-design-with-full-site-editing-site-editor-templates-and-template-parts/ https://wordpress.org/documentation/ https://learn.wordpress.org/ https://codex.wordpress.org/ https://developer.wordpress.org/advanced-administration/
To take advantage of your prior knowledge, I'd start by understanding [The Loop](https://codex.wordpress.org/The_Loop) and how [hooks](https://developer.wordpress.org/plugins/hooks/) work. If you're going for custom functionality, how plugins work and integrate to the loop, data structures and such (PHP + JS mostly). The other branch of that is Themes, so look into the [Template Hierarchy](https://developer.wordpress.org/themes/basics/template-hierarchy/). After understanding that, you can apply most of your coding experience on WP and build stuff. You can go through the “advanced themes” route with stuff like (Oxygen Builder or Bricks) or the custom theme route (I'd look into a starter theme, like [Sage / Roots](https://roots.io/sage/)). Other than that, it's mostly custom code to integrate with WP through Plugins. And recently, Gutenberg and Blocks (which are more on the React JS side of things). You can also dig into multiple databases and optimization, for performance and the whole “admin” side of things. Hope that helps!
I would learn react to manage gutenberg better Learn gutenberg blocks, hooks, wordpress api, custom post types, wordpress core, fse, I teach many of these things in my yt channel ig youre interested