Bring a large pot of water to a boil and cook the pasta according to package directions. Remove about ½ cup of pasta water and set aside before draining the pasta. Drain the pasta and set aside.
Once the pasta goes in to cook, drizzle the olive oil into a large sauté pan and bring to medium heat. Add onion and stir to coat with the oil. Cook for 2-3 minutes, stirring occasionally, until softened. Add the garlic and stir for 30 seconds until fragrant. Add the zucchini, yellow squash, corn, and green beans and sprinkle with the salt, black pepper, and crushed red pepper. Stir everything together to combine.
Reduce the heat to med-low and cover the pan. Cook for 5 minutes, briefly removing the cover to stir halfway through.
Remove the lid and return the heat to medium. Add the broth and the lemon juice and stir. Cook for another 3-5 minutes, stirring occasionally, until the vegetables are tender. Add the cooked pasta and stir to combine. Add the butter and the parmesan cheese along with reserved pasta water as needed (I used about ¼ cup of pasta water at this point, but you can add more or less, to taste). Stir until the cheese and butter have melted and all ingredients are combined. Simmer for a minute or so and then top with basil before serving.