If this topic is interesting to you, you can check out the sources listed at the bottom of this old post. They're good entry points for how the public relations industry developed.
https://www.thecut.com/article/marriage-divorce-should-i-leave-my-husband-emily-gould.html https://1ft.io/proxy?q=https%3A%2F%2Fwww.thecut.com%2Farticle%2Fmarriage-divorce-should-i-leave-my-husband-emily-gould.html To cope with the stress, I asked my psychiatrist to increase the dosage of the...
www.sosuave.net
Most primary sources on this topic are easily accessible in book form, as the propagandists liked to write. You'll become cynical afterwards, but you'll be able to properly read media as "What is this trying to convince me of?" and "What will the public believe is true after the popularity of this?"
I really should issue a warning here. I could identify many of these techniques on my own when looking at Iraq / War on Terror media when I was a teenager, so I had no real emotional attachment to media prior to reading Bernays. I just learned how the PR machine works with a similar logic as learning how a car works. And I didn't take it personally when I learned how my early political views came almost entirely from propaganda (eg. Family Matters -> "white people are racists", Aladdin -> "obeying traditions have no point to them", Simpsons -> "Christianity is a lie no one belives in", etc.).
For many others, especially those above 35, just leave the topic alone. This is where you get Flat Earth from. Notice how there are almost no Flat Earthers below a certain age. People learn they were used, take it personally, and have an emotional breakdown where they eventually reject common sense entirely.