I don't know where to start, but, here goes.
You shouldn't pick a competition weight until you determine where you are now. How old are you? How much do you weigh? What is your body fat %? Are you a natural athlete (no steroids, HGH, TRT, Andros, etc)? Where do you live? There are many drug-free-tested shows around the country scheduled throughout the year. You really can't determine yet how much time it will take to cut for your contest. Cutting may be easy for you, but cutting for a contest is something else. In order to be competitive at any weight, you have to be hard, lean, cut and vascular. And you have to show great symmetry and muscularity. What's your diet like? What's your training regimen? Lots of questions need answers before you are ready to begin prepping for your first show.