[creata]

Learn both. Rust first, because it's a lot more approachable. Modern C++ doesn't really have much in common with C to be honest.

Also, you'd probably have found these quickly, but cppreference.com is the nicest C++ reference (!cppref on DuckDuckGo) and doc.rust-lang.org (!rust on DuckDuckGo) has the Rust standard library documentation.

[joaquincabezas]

In some way I am stuck because I don't want to dismiss any of these (kind of Buridan's donkey) but planning this in a sequential way seems smart and would end the inner monologue