You can't 100% in one run though, "unfortunately", and even if you try to do ALMOST everything in one run, you need to plan your time veeeeeeeeery well. xD Good luck though!
That's why I'm using a guide, haha. I literally got exhausted of the first Palace because I did it all in one run after the introductory phases. Also, spoilers: I don't like how the narrative seems to be interrupted because everything you're playing right now is a retelling of the MC tot he prosecutor. It annoys be a bit. I much rather liked the past game's flow of constant present time, and not this back and forth.