What to do with such a spread of knowledge?

Question

Books

Now I practice in Python, Css, Html, Js. All knowledge is obtained from Youtube courses and "how to" articles. As a result, there were a lot of gaps in the knowledge of a particular language / technology. A little initial knowledge, a little from here, a little from there. And such a problem arises when reading a book on programming. I know half of the book, but I can't skip it because I can find missing information there.
But to read what you already know and hope to find what you missed...
It's the same with courses. The course lasts 3-6 months and the story with the book is repeated with it.
What to do? Skip, force yourself to go through everything again or practice?

Answer 1

Repetition is the mother of learning. In addition, sometimes the same knowledge, but presented from a different angle or in a different manner, is revealed more fully. So reread.

Answer 2

or practice?

Can. But for example, if you don’t know some element of the syntax (not to mention patterns or the like), then when you meet it in the code, at best, you will start to google to figure out what it is, at worst, continue to work in the ways that you know , because the time of the order or task is running out.
And what exactly is the problem? If there is a goal, then a large book can be read in a couple of weeks. It's just that during re-study, you skim through the material, just to make sure you know all of it. Stopping at unfamiliar moments.
Well, if you plan to develop yourself, then in any case you will have to learn new things, repeat the old, etc.