You have to set a goal of what you want to understand and why you want to understand it, then read accordingly. If your goal is to know the usual number of eggs laid by a bird because you are trying to identify one from its nest in your yard, sure just read some Wikipedia and maybe read its sources. If you need to understand a broad topic in the social sciences in order to do your job or organize politically, well sucks yo be you, you need to spend months to years getting a handle on the various schools of thought and approaching them humbly and critically, reading many books.

I'd usually start with easily digestible content like YouTube videos or ChatGPT. At this point, I'm not too concerned about the correctness of the information. It mainly gives me vocabulary that I can then look up for further reading along with the perspective of one or two individuals. That might be all I care about, and if so, I'd stop there and go on with my day. If I want to dive deeper, I'll look up textbooks and papers on the topic, or any other relevant primary sources. Basically do a light literature review.

Reading papers and contacting people in that field. I've found that university professors can especially direct you to materials in their field, and even like to chat about it sometimes. Half of my book collection was found this way.

The Internet.

Youtube u gotta get the widest set of opinions possible. Unfortunatly peertube just lacks content.

Um…read?