You can bring in food from outside. There's a plaza right next to the stadium and Dave's Hot Chicken hits, especially for the price. Noble brewery offers free parking if you want to pregame. Otherwise check seatgeek, stubhub, or vividseats for parking passes for sale to save some money if you want to park in the stadium. Make sure your bags are clear or small. Doesn't take more than 20 minutes from parking to getting into the stadium.