I don't want to be that guy, but...
On tattoos, Your 14... I've been planning mine since I discovered Dystopia in its (1 map only) stages. I plan On getting my first tat 3 years from now. Yeah, the cost is part of the reason, but when it comes to these things, you need to plan it for a very long time and really make sure this is you, really make sure you want to be a guy with a Bi-Pride tat, because 3 years down the road, you could look at your arm and decide "You know, this isn't me." Which brings me to...
On your Sexuality, your 14. You can really start exploring it with your 16-18. Hell, I know someone my age who still aren't sure what the fuck they are. You could realize, "Hey, I'm really not into dudes." five years down the road from now.
On love, Yeah, I'm probably the last guy to give advice on this, but if you really, really want to spend your life with 1 girl alone, you'll probably want a girl who's interested in who you are, here's something I read somewhere, "When you really want that special someone, you pretend your someone else, and then it'll all fall apart when she realizes your not someone else." Go for a relationship, but if she really, really can't get into the fact you like the idea of being with another guy too. Then I hate to say it, she may not be worth it.
When it comes to the sexy stuff like this, I generally find the best way of doing it is talking about it face to face. That way, when you say "Oh, I really like [so-and-so]." She doesn't just log off, hang up, and normally, doesn't give you a long pause before they try to understand it. But then again I've never sat down and talked with someone like that in your age group. Prepare yourself for a possible heap of inexperience in discussing stuff like this.
That's my attempt, Novixz. I'm no Dan Savage, but I think this should help.