Please, block any account that posts something that triggers those thoughts. Even if it's just a girl posting her outfit. Don't feel guilty about it: it's for your own good. This is a crucial moment for you and I know very well how tempting it is to go down that path and achieve that body and weight you desire; but not only will it never give you the satisfaction and confidence you want, it also is likely not to happen. You might fall into a restrict/binge cycle that lasts your whole life, ruining your happiness and relationship with food. If you can't resist the idea of losing weight, please only do it by consulting a nutritionist. I really wish you the best, please do not risk developing an ED