I'd start with introduction of philosophy books, you'll find them in any bookstore I reckon.
Plato's dialogues are essential for anyone interested in philosophy, not because Plato's right, but because how the dialogues are structured. You can learn a lot about how to figure out idea, pry and argument out of someone, seeing false arguments, etc.
Also, I found studying logic very useful. You can grab logic books, intros to logic at bookstores or online.
Finally, this video series of "An Introduction to Philosophy" which I found immensely useful:
You can find the rest of the series on his channel (starting on the last page of videos (page 15) and working through them. There are about 18 videos, which last about 30 minutes each)
Oh, and I only read 'Brave New World' and 'Island' by Huxley. I'll check out 'Doors of Perception' some time. Thanks!