What do people mean by you have to eat more calories than you burn? I thought the whole point of weight loss is to eat less calories than before and add exercise?

I'm 5'4, 176 Lbs. I eat around 1000 calories a day, and I do cardio. I now see I'm starving myself, and that's probably why I'm not losing anything(and if I do it's very SLOW). But I've been doing it like this for months. I noticed that I'm very tired and have a hard time concentrating.

How many calories should I intake each day, on top of my workouts, to lose weight and reach my goal of 130 lbs? How should I change this?

Thanks,
DisneylandFan