Lightly grease the Instant Pot insert. Set the Instant Pot to Sauté and add the ground beef.
Cook the beef on the bottom side until browned, then flip and break it apart with a spoon; continue cooking until no pink remains. Drain any excess grease.
Turn the Instant Pot off. Add the garlic powder, salt, Italian seasoning, black pepper, crushed red pepper flakes, and tomato paste, and stir to combine with the beef.
Break the spaghetti in half and add it evenly over the beef in the pot.
Pour in the water and the jar of spaghetti sauce, making sure the pasta is submerged. Close the lid and set to Pressure Cook (High) for 6 minutes.
Perform a quick pressure release when the cook time ends. Open the lid and add the softened cream cheese and grated Parmesan.
Stir until the cheeses are incorporated and smooth. Replace the lid and let sit a few minutes off heat if needed to fully melt the cream cheese, then stir again and serve.