WordPress site development

Hello to all
I manage a WordPress site
To develop this site, I want to learn programming language
But I dont know where to start
All I know is that I have to learn HTML well
What is the next step?

After HTML you’ll probably want to learn CSS, which is basically making HTML look nicer. After that, maybe JavaScript for user interaction, but I’m not sure.

WordPress templates are written in PHP. Depending on the extent of customization, the core languages you need to adjust your WordPress theme are HTML, CSS and PHP.

Gutenberg blocks are written in Javascript. If you want to add custom blocks to the stock of available blocks in the Gutenberg editor or if you want to add some animated design or interactive features to your theme, you need to know JavaScript as well.

But of course Content Management Systems like Wordpress are meant to be runnable without coding skills. So it depends on what you want to do with your WordPress site. You could find a theme with a bunch of customization options or use something like elementor page builder to design and build a site from scratch without having to do any programming.

Im a lead developer for a Google Agency. But your career path should be this

HTML - markup for all web pages
CSS - Styling for those pages
Javascript - Interaction for those pages.

Then once you have those under your belt you can move into PHP. Wordpress and all content management systems are built on PHP but you need the pre-requisites first. There is a PHP course in CodeCademy but it’s reliant on having a basic understanding of the above.

Once you have that you want to look into custom theme development, Wordpress hooks and the Wordpress API.
Best of luck.