If you need to know what 2>&1 means, then I would recommend shellcheck

It's very, very easy to get shell scripts wrong; for instance the location of the file redirect operator in a pipeline is easy to get wrong.

As someone who use LLMs to generate, among others, Bash script I recommend shellcheck too. Shellcheck catches lots of things and shall really make your Bash scripts better. And if for whatever reason there's an idiom you use all the time that shellcheck doesn't like, you can simply configure shellcheck to ignore that one.