First year-plus with a new kiddo and a new job is nuts. I'm guessing you are short on time and sleep both, which leads to mindless eating, eating convenience foods, and making food (and possibly brews) your new form of recreation.
First, stop trying to do every task at the same time. If you're eating, don't be working or watching TV or dicking around on rokslide. Eat, be mindful, and enjoy it.
Second, prep healthy food in advance when the kids asleep. Boil chicken thighs, cook whole grains like oats and quinoa, cook some sweet potatoes, and roast a couple trays of vegetables. Buy a load of whatever fruit you like. It makes mealtimes really easy when it's all right there ready for you.
Third, have snacks like popcorn (a great whole grain) or tortilla chips and salsa ready to go for between meals.
Fourth, don't go nuts with counting calories. Just remember that at the end of the day, half of your meal should be veggies and fruits (split about 60/40). The other half should be healthy grains and protein (split about 70/30).
Fifth, give up soda, energy drinks, and cut back on beer. Replace with water, tea, some fruit juice, and (limited) hard booze if you drink.
Sixth, be human. Nothing wrong with occasionally treating yourself as long as you're willing to pay the price. "Yeah, I'm gonna enjoy the hell out of these wings and this beer. But before bed I'm tossing on my headlamp and hiking hills for an hour."
Finally, if you have time to watch TV, you have time to throw in your headphones and go for a brisk walk. You totally have 30 minutes a day to walk.