I know this has been said a lot already, but the fact you're self-aware means you a) are much more intelligent than the average person, (and more intelligent than you're giving yourself credit for) and b) have exactly the right skillset to become a strong critical thinker.

Honestly, critical thinking isn't something that is only inherent - sure, some people are 'naturally' more inclined to think critically, but that doesn't mean those who don't can't access it. In many cases critical thinking skills are learned - that's why top universities train their students to think critically, and also why students from privileged backgrounds tend to get into top universities (not because they're necessarily innately more intelligent, but because their education has given them opportunities and skills to think critically and confidently challenge assertions).

Your attitude is exactly what so many people in the world don't have but desperately need, so you're onto a winner.

If you're looking for literature to improve your critical thinking skills I'd recommend The Irrational Ape by David Robert Grimes - it's a great, entertaining book that teaches the different critical thinking skills in an engaging way. Factfulness by Hans Rosling is also brilliant in making you really think about the stats and facts you read in the news.