How To Learn A Computer Thing
What is it? Programming language, framework, library, technology, concept? Do you want practical knowledge or general knowledge?
From Scratch
Find resources to start. Books, search for tutorials, YouTube videos. There’s lots of beginner material because there’s lots of people that have been beginners. There’s more beginner knowledge out there than expert knowledge.
Not From Scratch
Get up to speed. At first just as much as you have to to be dangerous. Find out what things are and, sometime more importantly, what they are not.
Make Your Own Notes. Refine And Review Them
Everytime you’re learnign have a page in front of you with space to write notes in. Label them. “Note”, “Question” (to answer later), “Important”, “Wow”. These will make it easier to review later.