Everyone is going to tell you pf tek bro. It's about as easy as it gets. Having just gotten into this hobby about 3 months ago I would say getting use to the new terms and jargon is one of the hardest parts. The other thing is understanding the life cycle of fungi. As most of us know, they are neither plant nor animal, so a lot of our assumptions about how life propagates doesn't necessarily apply to fungi. Having taken a few biology courses gave me a slight advantage, but not much. My professor did his dissertation on fungi, so naturally he interjected as much about it as possible into his lectures. On a side note, anyone looking to get into biology should consider focuses on fungi. We know so little about them there is a lifetime of research for anyone willing to take it on.
Personally, I've cruised most of the mushroom communities online. All of them abundant with information and for the most part full of helpful people, but I like mycotopia the best. One of the things that initially caught my attention was that anytime someone uses an important myco term, it is automatically linked with a brief explanation of that term.