THIS. Everything that you have said here, I completely believe in that too. If one observes the world and tries to find a pattern in it, the findings will align with this theory. Would you please share in which teachings exactly did you read about this. I mean specifically about the one where they state that God is the universe itself and not a person who is different from it. Was it the Upanishads? Is there some specific book or source ? Thanks for your input.

There's not a specific book where this information is laid out. I'll write what I know and can refer to source if you have questions. At the outset, I'd like to mention that there are dualistic (dvaita), non-dualistic(advaita) and qualified non-dualistic (vishishta-advaita) interpretations of the Upanishads. As a follower of advaita, I clearly see from texts that non-duality is what these scriptures teach.

The Mandukya Upanishad talks about "ajata-vada", ie the argument that nothing is ever born. Its teaching is very close to buddhist philosophy.

The Mundaka Upanishad talks about the creation being God itself. A famous mantra quotes an example of a spider which is not only the efficient but also the material cause of the webs that it spins.

Chandogya Upanishad chapter 6 has the "maha-vakya" i.e. great statement "tat-tvam-asi" - thou art that.

Of course, reading a translation will not be sufficient to understand the depth of this text. These texts are usually expounded by scholars who are steeped in the tradition of studying and understanding them. For advaita (non-dualistic) philosphy, the master-commentator Shankaracharya has written brief commentaries on all the Upanishads. Their translations are available in English, but like I said earlier, a mere reading of them may not bring about the desired affect of "oh my god this is so awesome".

This is very useful information. Thank You for answering.

You may find the extended lore of the Elder Scrolls games, of all things, to be interesting in relation to this subject. There's a lot of philosophical prodding at the idea of "world and identity as illusion", and at the nature of characters in fiction, and the ways those two concepts interrelate.

http://www.uesp.net/wiki/Lore:CHIM

http://www.uesp.net/wiki/Lore:The_Monomyth

http://www.uesp.net/wiki/Lore:Spirit_of_Nirn,_God_of_Mortals

It's ultimately not all that deep, but I'm fairly sure it's the only top-selling mass-market video game series to touch on the concept in even that much depth.