Creating this amazing dish is straightforward if you follow these step-by-step instructions:

1. Cook Pasta: In a large pot, bring salted water to a boil and add the fettuccine. Cook according to package directions until al dente.
2. Sauté Garlic: In the same pot, add olive oil and butter over medium heat. Once melted, add in the minced garlic and sauté until fragrant, about 1 minute.
3. Add Shrimp: Toss in the shrimp, seasoning with salt and pepper. Sauté until the shrimp turn pink and opaque, about 3-4 minutes. Remove shrimp from the pot and set aside.
4. Create Sauce: Lower the heat and pour in the heavy cream. Gradually whisk in the Parmesan cheese until melted and the sauce is smooth.
5. Add Crab and Italian Seasoning: Gently fold in the lump crab meat and Italian seasoning. Allow the mixture to simmer for 2-3 minutes to thicken slightly.
6. Combine Pasta and Seafood: Add the cooked fettuccine back into the pot, along with the sautéed shrimp. Toss everything together until pasta is evenly coated with the sauce.
7. Season: Taste and adjust seasoning with additional salt and pepper, if needed.
8. Garnish: Remove from heat, plate the pasta, and sprinkle with fresh parsley for a pop of color.

These steps will guide you in crafting this incredible One Pot Shrimp and Crab Alfredo effortlessly.