Somebody needs to RTFM ;) no seriously, Rust isn't something you can just jump into and guess what you're doing. Start with the official book and make sure you understand all of that.
IME the hardest part of Rust was learning the lingo to interpret compiler messages, and getting a solid grasp on references and borrowing. There is a lot more of course, like any language, but to me that was the steepest learning curve. I haven't used it in a few years tho, after losing all interest in programming.
-Bibi Goebels, basically