Trying to lose weight.

So I am not happy with my body. I am 16 and I'm 184 pounds. It's unacceptable. I want to go on a diet but it's so hard. I don't even know where to start. Should I got to the doctor maybe they can help me out with diet plans I don't know you guys have any tips? Because honestly I just don't feel beautiful my boyfriend says he loves my body and that he thinks is beautiful but I just don't feel it anymore.