having bags of frozen fruits/vegetables is an easy way to add them into meals. things like frozen mushrooms, spinach, and peppers can be thrown into pasta sauces, soups, sauteed dishes, etc. put frozen berries with plain yogurt into a blender and you've immediately got a healthy smoothie.
think of dishes you already like and think of ways to adjust them. it's easier to make healthy eating a habit if you branch off what you already know. love mac and cheese? add in mushrooms and peas. in the mood for chicken? roast a chicken breast on a baking sheet with peppers/carrots/onions. dress up a regular pizza with sliced tomatoes before putting it in the oven.
spend the evening on some recipe websites to get some ideas on what you can do. you don't need every single exact ingredient listed in a recipe to make it. if you have a day off, take the time to try cooking different meals. you'll have lunch/dinner set for the next few days and you can freeze the rest for whenever you don't feel like cooking. crock pots are cheap and allow you to throw in whatever you want in the morning, then come back in the evening to an already-cooked dinner.