BUILD SOMETHING.

Learning concepts without the ability to apply them are essentially useless.

Get your hands dirty and build something that would be valuable to you and solve a problem for yourself.

Don't get hung up on doing it "right". Focus on making it work. Don't worry about how it'll work for a million users. Right now your focus is on making it work for one user.

As you go you'll hit walls. Research how to get past them and keep going. Again, you're going to make mistakes. DO NOT GET HUNG UP ON THIS.

Making mistakes is part of the journey. Even the best software engineers in the world rarely get things right their first try. It's part of the process.

One thing i undervalued for most of my career was just reading code.

Get into the habit of digging into open source repos that catch your curiousity, and try to grok the way the project is layed out, what namespaces/files exist, what some of the core functions are, where the complexity is housed.

It’s all about getting exposure to patterns, especially if there aren’t other people to work with in your day to day.

Don't teach yourself complex software dev skills. Teach yourself complex software problems and learn how others have solved them in the past.

Like others have said, practice is key, however I'd like to add that you should not feel too discouraged if it feels like you're making no progress. You're probably making more headroom than you realize. At least personally in programming more than anything else I have occasionally only seen results after I came back to a concept I gave up on learning.

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Do be aware of getting stuck in local minimum though. I know it probably feels like bad advice but I figured I'd give it since it helped me personally, so maybe it might help someone else.

First focus on working on projects instead of improving your skills. The concepts you learn are usually a solution to some problem. Things are easier if you first encounter the problem yourself and then learn the solution, than if you do it in reverse. It is ok to do things poorly when you are starting out.

When you're at that point, it's usually a sign that you need to start applying what you learned. There are two parts of programming:

1. The concepts, the theory which is honestly the fun part.
2. Dealing with the little annoyances, setting up a development environment, learning APIs, wiring things together, running into problems there is no clean solution for and implementing something that works.

The second part feels unimportant, something you can always learn later, but it takes time to learn and get good at, and what you need to learn to start to effectively apply more advanced concepts. Otherwise you're learning things you won't be able to use.

Keep practicing.

Read other people's code, for example open source project. Contributing to open source can be good practice also.

Find a mentor.

Pick a team at work that has the skills and culture+capacity to mentor you.

By not learning. Software should be simple not complex.