Cook the Fettuccine pasta in salted boiling water according to package directions. Once the pasta is cooked, drain it and set aside.
In a small bowl, mix together the grated Romano cheese and garlic salt. Set this aside for later use.
In a large skillet over medium heat, melt the butter and add in the garlic. Cook for 1 minute, stirring constantly. Add in the white wine and let it simmer for 2 minutes. Stir in the grated parmesan cheese and cook for another 2 minutes. Add in the heavy cream and stir until the sauce is smooth and creamy.
Add in the cooked Fettuccine pasta and stir until everything is coated with the cream sauce.
Stir in the grated Romano cheese mixture and cook for 1 more minute.
To make the lemon butter shrimp, melt the butter in a separate skillet over medium heat. Add in the shrimp, green onions, garlic, and mushrooms, and cook for 3 minutes. Stir in the lemon juice and cook for 2 more minutes.
To serve, divide the Fettuccine pasta onto plates and top with the lemon butter shrimp.