Bring a large pot of salted water to a boil. Add spaghetti and cook according to package instructions until al dente. Drain and set aside.

In a skillet over medium heat, add ground beef and cook until browned, breaking it apart with a wooden spoon.

Add chopped onion and minced garlic to the skillet. Sauté until the onion is translucent.

Stir in crushed tomatoes, tomato paste, oregano, basil, salt, pepper, and water. Bring to a simmer and let cook for 15-20 minutes, stirring occasionally.

Add the cooked spaghetti to the meat sauce and toss to combine. Serve hot, garnished with Parmesan cheese and parsley.