Yeah it is Yoshi ^_^
So... sorry for being so slow in replying. Alsek covered a lot of the details, so I'll try and stick to covering things that he didn't.
If you don't already have one, you'll need a passport to get into the country. I have never gotten a passport, myself, but I imagine that it may take some time to go through the entire process of getting a passport, so you should look into that in advance.
The drinking age in the US is 21. While it may be legal for you to drink in your home country, you'll be underage here for another two years, and you won't be allowed to buy, consume, or be served alcohol while you're here because of that. There may be some other legal differences between where you're from and the area of the convention, but nothing else immediately pops out at me as being potentially relevant. If you have any specific questions, ask someone on the subject.
Cons (including MFF) generally have a First Con panel that covers information that's relevant to a furry con attendee's experience. Since you've been on a fursuit outing before, you'll likely already know the parts that relate to interacting with fursuits, but it also covers the 6/2/1 rule (at least 6 hours of sleep, 2 meals, and 1 shower for each day of the con) and how to handle the possibility of interaction with the media. This panel is usually early on Friday morning. If you don't expect to be able to make that panel, it's not a huge deal; the information covered isn't strictly imperative, and if you'd like to see it anyway, you can view the First Con panel of a prior con through Youtube beforehand (they're all pretty much the same).
Cons, especially big cons, have a very large number of panels and events, including Open Gaming rooms. You won't be able to see the entirety of what a con has to offer; given that, it's generally best to see the panels that interest you the most. In addition, it generally helps the first con experience if you go with or arrange to meet people that you already know, even if you only currently know those people online. You may find that you're having so much fun with old and/or newfound friends that you don't go to all of the panels that you were initially planning on attending. Don't worry too much if that happens; a big part of cons is having fun and socializing, and if you miss a few panels, you'll still have achieved that end.