Hey, I'm new here! Confused and Bisexual?? Need help pls!

Hey, I'm new here! Well, I don't really know how to start but I really need to talk about this. The thing is that I've been confused about my sexuality for years. I thought I liked girls until I was 12 or 13 but then I started liking boys. Actually, I liked boys more. So I thought that I was gay (because I had never been sure about my feelings for girls + I didn't really know what being gay was) and I didn't care at first (I didn't plan to tell anyone but I was ok with me liking boys) but then I started thinking that my family and friends weren't going to support me and I hid my feelings and sexuality because of that fear. So, for years I tried to live pretending that I didn't like boys and that I didn't feel anything (even though deep inside I knew that I still liked them) also I distanced myself from my family and friends, I didn't go out too much with them, stopped talking as much as I did...I just focused on my grades because studying was a good excuse at that time + my mum was diagnosed with bipolar disorder and she has been in hospital with depression almost every year since I can remember.
Btw, I've never been with a girl, no sex, no kissing (maybe my confused sexuality had something to do with me avoiding this sort things and running away when a girl approached)...now I'm not really into them because I'm more into guys.
I'm 19 and I'm sure about the fact that I'm attracted to guys (emotionally and physically) and I accept it. However, I'm not quite sure about what I feel for girls. For example, I can tell if a girl is hot or not, if I kinda like her or if I had the chance if I would have something with her but I barely get a boner looking at them, the sexual attraction is low(unlike it happens with some guys)Before I realised all of this, I didn't have a crush on too many girls, I think that I just "liked" the ones who nobody liked (maybe I just felt sorry for them?)But I don't reject being with a girl someday.
Another thing that confuses me is that I've always
watched and prefered straight porn (although most of the time I have my eyes on the guy ) I watch gay porn from time to time, but I prefer a guy on his own rather than 2 men having sex. Maybe this is the result of those years trying to hide that I like guys and pretending to 'be' straight, idk. What do you think? Btw, I started watching porn for the girls but thanks to this I realised that I liked guys better.
Lately I couldn't stop thinking about all of this and that's why I came out to my best friend a couple of weeks ago because I knew that she would support me and accept it. I knew that she may supposed that I wasn't straight because she never asked me about girls nor I didn't talk about this kind of things. She was accepting and nothing has changed between us but I feel like everything is like it used to be because we don't talk too much about it (it isn't a big deal for her but I wish we talked more about it because I need someone to talk)
I want to come out to my parents and friends next year (my next year's resolution) I think that they will be ok, not sure about my grandparents and a couple of friends though. But since I'm not a 100% sure about my sexuality I don't know what to come out as. If I'm not even sure about who I am, how am I supossed to explain them this? I don't want to hide anymore but this is stopping me. Any advice on how to come out to them? How to figure things out? I know that time is the key to find myself but if it takes ages?
I think that was all, thanks in advance, sorry if the post was too long and sorry for my english, obviously it's not my mother tongue. <3
It's weird opening myself to you here but I feel so good now

 

¡Muchísimas gracias por contestar! La verdad es que ya había pensado en intentarlo con alguna chica, pero cuando llega el momento me bloqueo, me da miedo y un poco de ansiedad (siempre me pasa cuando tengo experiencias nuevas). Quizás en el fondo pienso que no es lo correcto para mí y que simplemente soy gay, que sería lo más "fácil" para mí, pero no estoy seguro de nada. Además, me gusta un chico de mi universidad y creo que le puedo gustar, pero no estoy seguro al 100% de que le gusten los chicos...Y para tener algo con él tendría que contar a todos que no soy hetero y como que no me veo preparado xD(aunque he ido dejando pistas) y para mejorar mi situación: creo que una amiga suya intentó algo conmigo hace unas noches -.-
Y de nuevo, muchas gracias por contestar porque no tenía a nadie con el que hablarlo y tu mensaje me ha venido genial.
¡Espero que te vaya bien y que salgas de dudas pronto!