Where to start?

Losing weight for me is hard, it's the time I don't really have. I am 4''10 and I weigh 150-155. I have not been eating so well either. For me being so small a lot of people think I'm pregnant and I'm not. Before I gained I was 90-100 and was fit. Obviously we all go through things and sometimes hit depression. So I want to start soon but I just don't know what and how to start ??? Any suggestions ???