Learn Bash

Learn Bash. This is the lowest barrier to entry to start automating something anywhere.

But if you can, avoid Bash and use a real programming language, one you would want to write your growing code base in.

A great solution is to use Haskell with the Turtle library. Together with a nix-shell sha-bang, this is the perfect starting point for greater things.

Read: Manual work is a bug

Related: Sha-Bang