Probably the best thing is to start with something that has a solid story but won't overwhelm you with anime jargon, and there "Fullmetal Alchemist: Brotherhood" is pretty much impossible to criticize - it's got a real plot, characters that actually develop, and the first episodes hook you without needing to know anything about otaku culture. If that doesn't appeal to you because it seems like too much action, then "Attack on Titan" is another option that works well for people your age, or even "Death Note" if you want something more focused on mystery and psychology than on fights. Either way, don't pay attention if someone tells you that you absolutely have to watch certain anime - what matters is finding what hooks you, because there's something for everyone in this medium.