In a pan, heat about 2 tablespoons olive oil. Sauté the shrimp and fish on all sides. Season it with salt and pepper and place it in another dish. In the same pan, pour in a little more olive oil and fry the onion and peppers, then add the garlic and rice. Stir thoroughly and pour the wine in.
Pour the saffron in the chicken broth to dissolve it. As soon as the wine is absorbed by rice, pour in a little of the broth with the saffron and add the peas. Once the rice absorbs the liquid, add a little of the broth at a time, until there's about 1/4 of it left. Finally, add mussels, shrimp, fish, and the last 1/4 of the chicken broth.
Add salt to taste, mix well and cover it with aluminum foil. Bake in a preheated 302°F (150 °C) oven for about 20 minutes until all the liquid is absorbed by the rice. Once removed from the oven, leave the dish covered for 5-8 more minutes.
When serving, sprinkle with lemon juice and parsley.