- Cook the fettuccine according to package instructions until al dente. Drain and set aside. 
- In a large skillet, heat the olive oil over medium heat. Add the shrimp and cook for about 2-3 minutes on each side until pink and opaque. Remove the shrimp from the skillet and set aside. 
- In the same skillet, add the minced garlic and sauté for about 1 minute until fragrant. Stir in the Cajun seasoning, salt, and black pepper. 
- Pour in the heavy cream and bring to a gentle simmer. Stir in the Parmesan cheese until melted and smooth. 
- Add the cooked fettuccine, shrimp, and crab meat to the skillet. Toss to combine and heat through for about 2-3 minutes. 
- Remove from heat and stir in the chopped parsley and lemon juice. Serve immediately.