Others have listed a bunch of good resources. If you are more of a visual learner, I have heard good things about the Easy Rust videos - https://www.youtube.com/watch?v=-lYeJeQ11OI&list=PLfllocyHVgsRwLkTAhG0E-2QxCf-ozBkk

On KDE you can try out Polonium, which integrates with the native tiling support and makes it awesome!

Yes, my thoughts exactly.

This problem is not solved by monads, but by higher kinded types in general in languages like Haskell. They give you a uniform way to be generic over effects like async (Async) vs sync (Identity). Both of these can be treated as (F) for all A. So a generic Into would look like the following, and no special syntax or semantics would be needed. The type system (if sound) would prevent you from misusing a trait like this.

trait Into {
   def into(self): F;
}

This seems to have many similar ideas as Dhall Lang - https://dhall-lang.org/