Preheat oven to 375°F (190°C) and line a rimmed baking sheet with parchment paper.
In a large bowl, combine ground beef, breadcrumbs, grated Parmesan, eggs, milk, onion, garlic, oregano, basil, salt, and pepper.
Mix the ingredients by hand until just incorporated, being careful not to overwork the meat.
Form the mixture into a uniform 9x5-inch loaf shape on the prepared baking sheet.
Spread 1/2 cup of marinara sauce evenly over the top and sides of the meatloaf.
Bake in the center of the oven for 45 minutes.
Remove from oven and spread the remaining 1 cup of marinara sauce over the loaf, then top with shredded mozzarella cheese.
Return to the oven and bake for an additional 10 to 15 minutes until the cheese is melted and bubbly and the internal temperature reaches 160°F (71°C).
Allow the meatloaf to rest for 10 minutes before slicing to ensure the juices redistribute.
Garnish with chopped parsley and serve.