[grawp]

https://www.rust-lang.org/learn and there is a whole official book with detail explanation and first principles about what you ask.

Learn to use obvious "entrypoints" first which are cmdline help, manpages, and official web documentation instead of searching the web first. Those TONS of tutorials about embedded rust are uninformative at best and actively harmful at worst.

If you plan to use Cortex M based microcontrollers then there is rtic.rs async framework / RTOS. It could teach even 95% C programmers how hopelessly underused/misused NVIC in those core usually are.

Then if you need drivers with bells and whistles there is another async framework / RTOS called embassy-rs but you can combine those drivers and subsystems with rtic.rs async engine.

EDIT: Don't imagine async engine on MCU as some costly abstraction. It's zero cost abstraction for embassy-rs when compared to traditional RTOSes and negative cost for rtic.rs since traditional RTOSes does not use dedicated hardware machinery for scheduling which is present in Cortex M cores.