Cut the half of the lemon in half, squeeze the juice from one part, and cut into slices to the other. Cut the parsley. Mix everything and add a little pepper.
Chop the garlic and fry a little in butter, add the peeled shrimp, salt, pepper and cook for about 5 minutes until the shrimp turns pink. Add parsley with lemon and remove from heat.
Boil spaghetti in salted water with olive oil until tender.
Drain the water from the spaghetti and put in the pan to the shrimp, mix well. Shrimp spaghetti ready, serve warm.