Haskell is unreasonably effective at writing CLI applications. I haven't worked on it in a while, and the code is not the best, but this is what I built when I was starting out:

github.com/joelmccracken/reddup

https://haskellbook.com/ is how I got good at Haskell. If you can't get a copy, there are other ways to get good at it though! Just not necessarily any all-in-one resources.

I'm always willing to help folks learn Haskell tho, so if you have any q's get my email from my bio.