Are there any good books/resources to learn functional programming for a beginner?

I know the syntax for like 5+ languages but I've never made anything beyond simple command-line programs.

I recommend Structure and Interpretation of Computer Programs by Sussman and Abelson. By the end you'll have learned functional, procedural, and object-oriented programming, and how they're related.

Both the book (https://mitpress.mit.edu/sites/default/files/sicp/index.html) and a series of video lectures based on it are available online (https://ocw.mit.edu/courses/electrical-engineering-and-compu...)

This Cornell gitbook is creative commons licensed and teaches both functional programming concepts and OCaml datastructures

  wget -mkEpnp http://www.cs.cornell.edu/courses/cs3110/2018fa/textbook/

Plus this talk https://www.youtube.com/watch?v=DM2hEBwEWPc Effective ML is interesting, shows how to better write ML family programs so other people can read them, and making illegal states unrepresentable where he talks through splicing up interfaces to make them more robust by taking advantage of the type system.

Thinking Functionally was an OK book. We use Haskell and I’ve found Haskell from First Principles and Learn You a Haskell both to be very good for learning not only the language but functional programming in general.

This. You might not need it, but the more paradigms you learn, the more easily you’ll be able to learn a new language for work. Once you’ve got the main paradigms down, learning a new language is basically just learning the syntactical idiosyncrasies.