Firstly, I think you need to slow down! :] I know it's confusing and everything, and you're trying to figure out who you are, but even if you are gay, or bi, or even straight, it doesn't matter. You can cross that bridge when you come to it, first you've got to figure out which you are.
Ok, so you live in a place that's pretty limited. Well, pulling a guy or having sexual relations with someone isn't something you need to do to figure out who you are. Generally, most people find out they're not straight around 15/16 when they haven't had many, if any, relationships and haven't had sex, with either a girl or boy. So, don't worry about being in a place without a thriving gay scene, that doesn't matter. And anyway, people that are straight don't need to have had sex to know that they're straight, gay people are no different.
Now fantazing about boys could simply mean that you find them attractive, and that's that. But, personally I think being capable of loving someone is a mixture of three things; physical attraction (finding them pretty), sexual attraction (thinking at some point you'd want to have sex with them) and emotional attarction (being able to talk and just, be with someone). They're not rules, just my opinion. So, ask yourself, do you think you could have that with a man? Sometimes finding that out comes from finding out the feeling you have for a guy is a crush, sometimes people just know, sometimes it comes from experimentation. Most of the time, it takes just that, time. So, be patient with yourself, but have a think.
And coming out. The first rule of coming out, saying that you are definately this or that to people, is that you accept it yourself, and realise it's not a bad thing, and nothing to be ashamed about, that it's perfectly normal. But, given you don't know what you are, I would strongly recommend against it. However, if you feel you need to talk to people about what your thinking, that make sure it's someone that you have confidence in and can trust. Personally, talking to gay/bisexual people got me comfortable with the idea, so, I'd recommend surfing the net for forums. thegyc is quite good but Queeryouth i'd say was the best. Also, this is a good way of accepting who you, which, as you've said is something that may scare you.
On that point, gay/bi people are pefectly normal and indifferent to anyone else. We have a laugh, go to school, and have relationships. Nothing new. And, this "typical guy" thing. Well, not being a typical guy isn't reason to think youre not straight. Who you are isn't defined by your sexuality and making stereotypes is a very bad mistake. Some gay guys are camp, introvert, extrovert, loud, shy, skinny, muscular. Some you'd never guess they were gay. So, do't judge a book by its cover.
Oh, and this girl. Well, telling her things that, to be blunt, means you've been finding other people attactive, I can imagine to be a nice thing for her. So, as much as I know you want to tell her, becasue you're close to her, it might not be the best thing. Do you think a relationship if the best thing right now? Tbh, I think on this point I'm not someone that can give you much advice, so maybe try those sites out.
Hope I helped!