You know the embarrassment. You tell someone about this amazing book you read some weeks ago and then they ask what it's about and you're like "uh, finance and um, bitcoin, you know".
To intentionally learn from books and articles (and to avoid the above embarrassment), I've developed a process to remember what I read.
First I tried highlighting sections I wanted to remember. This didn't help.
A big improvement was rewriting the highlights in my own words. It made my connection to the writer's ideas stronger and more personal.
The next level is extracting the underlying ideas from the highlights. Most books contain no more than 3 new ideas (often just one!). I write down each idea together with the most striking example. Including an example matters because our brains remember stories better!
Finally, I turn these ideas + stories into (digital) flashcards. On one side, I write a question like, "which idea does this story represent?" or "tell a story conveying this idea" and then the answer on the other side. I also use gap sentences: replace a keyword in your notes with a [...], which you then have to recall (answer: gap).
I practice the flashcards using spaced repetition: a system to review the flashcards at the exact moment you're about to forget.
Using this process I can summarize a book in just a few sentences and stories, which is just about enough to apply some of the ideas in real life.