New, short, and a few questions?

Options
HEEEY! I need encouragement! I signed up around two years ago and now I'm back, with a tiny bit more motivation.
So friends please!!!! I'm 5ft 1" so for my weight I look a LOT chubbier, my face and arms are annoying...
Also, how accurate is this website at guessing how much you can lose if you stick to the goals? And any useful weight loss tips guys?
Thank you!!!!!!! xx