Losing weight, gaining confidence.

I would just love some advice on getting fit again. I want to start walking/jogging daily, I'm on day 3, and try and cut back on junk food. It's kinda hard for me to not eat junk when I'm working with food daily and get sweet discounts when on the clock. I just want to be able to at least wear shorts again without feeling like a whale with cellulite. I never stick to my exercise and dieting plans though. If they last more than a week that's honestly a miracle for me. How can I lose this weight and gain my confidence back?