i go to uni in brisbane and i'm currently visiting my family in shanghai. i've lived in china for like 11-12 years cumulatively.
definitely go to yang shuo or just do some research into some of the rural areas and see which appeals to you.
uh language, the tones are the hardest part, as english is atonal and chinese has four, so don't be surprised if locals have a lot of trouble understanding you. moreover, a lot of country accents make their mandarin extremely difficult to understand.
in terms of food, basically just go as adventurous as you want to be. some stuff might upset your stomach but if you like it you should eventually get used to it. another big thing is spicy food, for a lot of stuff you buy off the street you can get it spicy or not, so make sure you learn to say no spicy or less spicy if that's a big deal.
some mainstays of chinese street cuisine - stir fry (rice noodles, rice, specialty dishes), meat (and other things) skewers, baked sweet potato, cold noodles (summer), pancakes (with a variety of eggs, vegetables, sauces, etc), soup noodles, claypot glass noodles.
i know this might just seem like common sense but don't give / lend money to anyone who asks. there are a lot of swindlers who'll ask money for bus fare or claim that they lost their wallets or whatever. always lock your shit up like bikes / don't leave bags around.
when buying shit in markets be prepared to bargain, being a non-chinese speaking foreigner, vendors will try and charge you at least 200% their going price. immediately slash their offer in half (learn numbers or bring a calculator).
china is a really fun place, and while the expat culture is pretty obnoxious, it's also really fun depending on how much you embrace it (cheap things, no one cares unless you break something or hurt someone).
drop me a vm / pm if you have any other questions