Nim is one of supported languages on Exercism - free and open source platform for coding exercises.
A brief introduction to Nim by Exercism
Nim in 100 seconds by Fireship
Computer Programming with the Nim Programming Language - One of 3 books about Nim and the only free one.
Summary of Nim features and resources. Warning! AI-generated, so don't rely on it too much.
Nim by Example. - Useful for quick syntax overview
Official Curated List of useful packages
Example of making a real program in Nim (brainfuck interpreter)
How to build and deploy static binaries with musl
Nim is not a transpiler