Hi Vishal,
I took my test on October 10, and I passed with Above Target in all areas! So hang in there, don't get discouraged!
I do have a suggestion, which helped me a lot. I found this guide
ricardo-vargas.com/downloads/pmbok6-processes-flow/
and downloaded the Process Flow full and simplified versions. I studied both, but used the full version a ton. I printed it out in such a way that I made a poster taped together! It is grouped by process group rather than knowledge area, which for me with the way my brain works, made MUCH more sense. I also watched his video on that very same web page (entitled PMBOK® Guide 6th Ed Processes Explained with Ricardo Vargas).
To do better with my ITTOs, I got serious about focusing on the very unique inputs and outputs of note that only occur as an I/O for one process. I made little flashcards to drill this into my head. Also, when I looked at Ricardo's process flows, I was able to see the whole picture at once and was able to see some patterns with ITTOs (like for example, that every Plan ______Management task has the Project Charter as an input). There are many other patterns you might start to notice as well, and it makes it a whole lot less overwhelming to think about ITTOs.
Hope that helps, and good luck to you! You can do it!