There's some overlap, but yea it's really not how things work.

If you're in the US, UK, Aus, Canada, etc, the common law system in use is fundamentally quite different.

> I mean any set of resources that after studying it will make you confident in reading material in law. It doesn't necessarily have to be a specific law system, or is that not how things work?

That's mostly not how things work, at least if you mean to imply “justifiably” before “confident”.

Law isn’t physics where there is a universal underlying truth; it is a social construct, and each system of law is its own construct.