Hi Christopher, I am at guitar fundamental 1, just starting the key lesson. And also thank you for your answer, I will go through those links and do more practice.

So I actually played guitar before, but then I kind of drifted away from it, now I feel like I want to take it seriously, and I always use the 6th and 5th string to find the key and chords, but learning music theory makes me think if there's a systematic approach within the concept of the music theory itself, well, it's good to know that I'm on the right track.

And again, thanks for your help, appreciate it.

Cheers :)