Thank you for asking a question that allows me to reflect. For me the thought occurred during a time in my life when I was traveling for an extended period outside of the US and was thinking a lot about things. I had always had an intuition that citizens of the US were being misled, and I realized that I didn't understand anything at all about why some people became powerful and some people didn't. I was hanging in Berlin with friends and just decided silently that it would be an informal, albeit lofty, goal: to figure out just what on earth was going on with power. I do feel that I have come to understand the dark side of power better. The "conspiracy" theoretical standpoint has been really useful for me, although it is probably not comprehensive, and leaves much to be understood.
As far as sources...yeesh. I don't think there is any one source you can trust. For me, it all started with utilizing multiple sources (a lot of youtube videos, but also reports by organizations such as Architects and Engineers for 9/11 Truth, for example) to understand 9/11 as a false-flag operation (and not only that, it was an occult ritual, but I didn't understand that until much later).
But, to answer your question directly, if you're looking for sources I trust, I would first tell you to look to James Corbett at Corbettreport.com. He has been working for a long time, but his journey started probably much where yours is, so if you're new to the journey you might want to use the search bar to search for specific issues/events/terms. If you're interested in the more esoteric stuff, I really appreciate the work of Mark Passio at whatonearthishappening.com. To contrast, I have realized that I don't trust the BBC, or NPR, or any state-sponsored media. They might put out some great programs, but they are a mechanism of control, just as much as FOX, CNN, and all the others are. I read/listen to those outlets with a big grain of salt, always.
Also, it's so unfortunate and ugly but the ritual abuse of children seems to be a running theme in powerful circles. Of course the general public knows about the Vatican (institutionalized religious sexual abuse), and Weinstin (institutionalized entertainment sexual abuse), and Epstein (blackmail-able abuse). The general public doesn't seem to have been connecting these dots. But there have been other, very powerful instances of this kind of behavior, including the Hampstead case, the Lithuania case, etc. etc.
I hope that you will be careful about your own mental health if you choose to look into these things, and I hope that it helps you to make up your own mind about what power is in today's world. We all have our own ideas, and you are very entitled to make up your own mind.
I don't mean to weird you out or make you sad. As a pretty sensitive person myself, I have gone through a lot of heartache realizing that the world isn't what we've been sold. But I think that, if you feel ready for it, it's an important journey. Let me know if you want me to clarify anything or if you're feeling shitty after learning about the sex abuse stuff. It's super rough, and don't go into it if you're not feeling ready (I probably wasn't ready, and it fucked me up for a few years.) Oh, this world. Peace and love to you, friend.