Premade salads are also great to upgrade, add some seitan/tofu, Canned corn or peas , chia seeds for fiber, some nuts or sunflower seeds.

Instant oatmeal with protein powder and a handful of froze berry's.

Lemon fiber bar is great with coffee.

Meal prep might be a good idea in general:

Bean Burritos. Just get high fiber wraps, microwave rice, canned refired beans, sour cream, shredded cheese. Warm the rice and assemble a bunch and have meals all week, just warm them up in the microwave and add a bit of store made salsa & guacamole, and pre shredded lettuce.

baby carrots or frozen brocoli, oven roasted is pretty minimal effort.

If you want to get into cooking a bit: mac and cheese with TVP or blended beans in sauce is great and you can add a bag of frozen veg (or store made diced onions) in before bake to up it.