You should mention where you will be going, and the type of accommodation you're booked into. Many places are relatively isolated and self-contained 'resorts'. There won't be any restaurants to go to - all the eating is at the resort itself .. they'll have a meal plan.
I don't drink much .. most often a beer or two in the evening, and a Fiji bitter was probably in the FJ$2 range, I can't recall exactly, but nothing which I felt put a dent in my daily budget. So I wouldn't worry about that.
It a different story for the hard drinks and wine, etc that you'd get at the resorts. I've seen and heard reports from people who recommended bringing in their quota of duty-free alcohol - apparently the markup in the resorts can be substantial.
Only the bigger towns will have restaurants to choose from, and most tourists do not spend any time in the major towns. The result is that most restaurants you will find are aimed at the local pocket -- so meals are on the budget side. If I ever paid FJ$15 for a single suppertime meal it was a lot. If I was in a town and bought both lunch and supper in restaurants (chinese-type stir fry etc most common, fried fish and taro, etc), then I was usually paying under $FJ15 for both. Maybe a 'mid-range' would average FJ$5 more -- I didn't notice a huge budget-to-midrange difference. I wasn't really checking, as I focused mostly on the budget level. Sometimes 'budget' was all that there was. I wasn't looking for high-end restaurants so can't comment on the prices in such places - they'll likely be in the upper-end hotels, if anywhere.
Internet cafes .. again, it will make a huge difference, depending on where exactly you are. You'll only find internet cafes in the larger towns. More important, cost is not the thing you should worry about. The big practical problem is speed, or lack of it. A lot of internet connections are only phone line modems and can be painfully slow, to the point that the connection can time out before you can open an email account,etc. So, while a modem connection might cost Fiji$2 an hour, it would be more economical to find a cafe with a fast connection and pay Fiji$4 an hour. You'll get more done that way, and in the long run probably pay less.
In the outlying places about the only internet connection you'll reliably find is in dive shops, not internet cafes. So you're stuck with whatever price they ask. But it's usually fair, a bit more than in a town but not much.
