I am planning on becoming really good at playing the guitar but i love playing guitar hero too…would that be weird if i was really good at the guitar and played guitar hero still?

I bought a guitar because I’ve always wanted to learn and very dedicated to following this through. I can’t seem to understand the finger positioning or exactly how it all comes together. I have a book "idiots guide to playing guitar" but I’m wondering if i should take a couple "in person" lessons with a teacher. Has anyone actually learned on their own? How long until you got the hang of it? I’m not expecting a fast transition into being amazing, just some helpful thoughts. Is it too hard once you get the hang of it? Lessons?