Wanting to know about Zoroastrianism.

So, I'm just a student and I like formal science (maths, logic) and philosophy, it kinda got me back into religion to as hinduism at its core talks about the logical conditions for anything to exists as a god. then I've read about Buddhism too, it just says there's no rule, every condition depends on another condition and it goes on without a foundation. i wanted to know about Zoroastrianism, like what's the core philosophy, I'm not really into any tradition religion stuff like art or god's but more into philosophical side of it. i wanna know introduction of Zoroastrianism from its followers as who can better define it than themselves.

all I know is that all persia, india were pretty connected that time and there were alot of cultural exchanges, so I hope to find similarities between them.

also I didn't knew there were a fairly well community of Zoroastrianism, are you guys also from India? by far india has the largest population so I guess that's the case but I've heard that in Iran people are also moving towards atheism or towards their roots into Zoroastrianism. is that true?