Im not an art teacher, only interning as one, but i can say from my experience with learning to teach that there is nothing more frustrating to a person who is trying to help someone, than to be attacked. It's even worse than when a student ignores advice entirely without pausing to consider it. Im not going to point out all of the strikes you have against you from this thread alone, suffice to say that they are numerous and might be difficult for you to work around as you continue working.
heres my suggestion:
1: folow all of the advice given about drawing regularly and practicing before taking on ambitious pieces. I've been working with oils for about a year, but that doesnt mean im going to try to be rembrandt van rijn. dont talk yourself up, no matter how enthusiastic you are about your artistic future. Michelangelo di Lodovico Buonarroti Simoni, Pierre-Auguste Renoir, Albrecht Durer, Pieter Bruegel, Frederic Edwin Church, Winslow Homer, Worthington Whittredge, Jacques-Louis David, these are men who could be considered "very good at art." When you have permanent installments in the Louvre AND the Metropolitan the way these men and select few others do, you may brag.
2: post your references if you use them, so that people can have as good an understanding of what you are striving for as possible
3: strive to make youself understood in an appropriate manner. perfect grammar is not necessary, i see it as a bit of a chore really, but you do need to try a little, because if you cannot be understood, then you cannot be assisted in any way
4: remember that, no matter what is being discussed, this forum is at the core a community which exists purely for the benefit of the greater human good and that asks for nothing in return but a minimum level of respect and coutesy. we all get offended, or nervous, and sometimes feel inturded upon, especially in critiques, but one of the things i know that i have learned here is that the people of this community are good-willed and not in any way malicious and there is absolutely no reason to react to them as such.
5: search for references like the one lawrence posted to help you. also, look online for traditional drawing tutorials that will help you as well, these are not the best but they do help some.
also, try looking for art classes near where you live. i dont know where you live, but RISD in Rhode Island, SVA in New York, CCA in the san francisco bay area, and many other schools have fantastic Continuing Education courses for young artists taught by faculty or adjunct professors. I personally can say that the RISD CE courses and the CCA precollege summer program (which you are still a bit too young for though) are excellently run opportunities to expand your horizons.
best of luck
