C++20: Ranges and Coroutines on Embedded

I'm trying to get my head around the new C++20 ranges library and coroutines.

In particular, I would like to understand whether we can use those on a bare-metal Embedded platform, let's say STM32. It boils down to these three questions, basically:

1. Do coroutines depend on any OS feature?
2. Are coroutines needed for using the ranges library, e.g. iota()?
3. Does the range library rely on heap allocations?

thanks, Steffen