Bring a large pot of salted water to a rolling boil over high heat. Add pasta and cook until al dente, about 8-10 minutes. Drain and set aside, reserving some pasta water.

Season the chicken breasts with salt, pepper, garlic powder, and Italian seasoning. Heat olive oil in a skillet over medium heat, and sauté chicken for about 5-7 minutes per side until golden brown and cooked through. Let it rest before slicing.

In the same skillet, add more olive oil along with chopped zucchini, yellow squash, and minced garlic. Sauté for 4-5 minutes until vegetables are tender but still vibrant.

Reduce heat to low, add butter and lemon juice to the skillet, stirring to create a creamy sauce. Toss cooked pasta with the sauce until evenly coated.

Return sliced chicken to the skillet with pasta and vegetables, adding half of the Parmesan cheese. Stir until well mixed and heated through, about 2-3 minutes.

Plate the Lemon Chicken Pasta and sprinkle remaining Parmesan cheese and parsley on top. Serve immediately.