How are programming skills commercially in demand?

Question

Career in IT

What technologies/programming languages/algorithms do you need to learn to start earning from $1500 per month?

I have the following background behind me: I
studied at the university as a programmer (I studied secondary), I graduated 5 years ago. After graduation, he went into sales.
Then he opened his own web studio, was engaged in the development of sites / Internet advertising. I did some of the work myself, delegated some of the work to freelancers.
During the crisis, the price tags for websites fell, and I could not enter the high-budget development market. It has become unprofitable to deal with landings and business cards on WordPress.
Now I decided to go to work for hire and develop myself as a programmer.

What I know now:
HTML5/CSS3/JS/jQuery/AJAX/Bootstrap at the frontend level for business card sites and landing pages
Wordpress/Opencart - at the level of
PHP theme development - at the level of functional programming of complex SQL parsers
- at the level of writing popular queries
I also partially remember OOP, I understand regular expressions well. I have experience working with the API of various services.
I understand the documentation quite fluently, incl. in English.

There is a foundation of knowledge in the form of algorithms and applied mathematical disciplines (though they have already been forgotten). The question is where to go next? What do you need to remember and what technologies do you need to learn in order to become a commercially demanded programmer?

Answer 1

Look at the requirements for vacancies for the position you are interested in and think about what you are missing.

Answer 2

Good skills are in high demand, bad ones are bad
I know people who earn much more than $1500 on website development

Answer 3

At a minimum, understand the difference between functional and procedural programming.
Further, to become commercially successful, you need a baggage of practical experience. Therefore, I would advise you to pull up OOP, regular expressions, design patterns, get acquainted with some framework and get (at least) a junior in an office --- just to gain experience. Growing up alone is hard.
However, there is an alternative way: to team leads. Somewhere you can almost immediately go to the team lead, somewhere you first need to work as a developer.
In any case, experience can only be gained by working on a real project, solving applied problems.
And yes, growing from junior to senior is hard and difficult. Regardless of your talents, the path will take at least 5 years. Deal with it.
Or wait out the acute, crisis period and open the studio again. Or go freelancing, but there the experience of programming (and even more so development) drips more slowly.
Everything I said above --- IMHO.