One of the most exciting things about being a software developer is also the greatest cause of stress and anxiety: the constant changes.
Always a new library, a new framework, a new concept, a new way to do something. A friend of mine, also a developer, once said to me "dude, sometimes my brain hurts from all the learning".
I have worked with super-smart and talented developers. The ones that know so much and think so fast that they make you feel like an old 486 vs a 32 core processor. Maybe, they have some chances to keep up with all the moving parts. Maybe.
But most of us are not like that. We can't keep up with making cool stuff with CSS, learn all the JS Frameworks, be up to date with what happens on the backend side and meanwhile also write a GraphQl open-source library while you play with the latest machine intelligence tools.
So one thing you can do is to specialize. Pick your battles!
Find what excites you. What drives your interest. For me, it was the mix of front-end development, a bit of design and a passion for building products.
I know how to make a SQL query, but I could not care less for how well the DB is optimized. I don't care what we use for continuous deployment or how we host our stuff. But I love implementing a new design, simplify the CSS, attracting new users to the product and see the charts go up.
Also, focus on the things that don't change. The ones that are here to stay. Security, CSS, SQL, responsive design and so on.
Indeed if you are a beginner, and after you get your basics up, spend some time experimenting. See what types of problems are interesting for you and give you pleasure to solve them.
But, in the long run, I've found that it's a better idea to be very good at something and, more or less, ignore the rest. You will get better jobs and feel a bit less anxious in trying to keep up will everything.