Need help before going back to school?

I'm starting high school in about two weeks. I was hoping to lose a lot of weight during the summer, but that didn't happen.. I want to feel comfortable with the way I look. I also have acne… and washing my face does nothing. Along with the numerous facial products I have tried. Do you have any.. I guess I'll call it beauty tips.. that I can try? I would really appreciate it. How I can look thinner and stuff that would help my skin.