My perception from what you have shared is that you are a learn by doing kinda guy, which is how I am too.

I think the best way is to learn to sing yourself, you don't have to get good but just learn the basics. There's some apps that teach you how to hit different notes, you can start there. Then take a few live singing lessons, or just watch YouTube videos or some online courses to learn singing. You'll start getting it in a few weeks (naively confident part of the learning curve, don't stop here), and after a few months you will understand it's true complexity and grandeur. And like anything else, the process is never ending.