Prepare the pizza dough by combining flour, yeast, sugar, and salt in a large bowl. Gradually add warm water and olive oil while stirring, until the dough comes together.
Transfer the dough to a lightly floured surface and knead for about 5 minutes until it becomes smooth and elastic. Form the dough into a ball and place it in a greased bowl. Cover the bowl with a clean kitchen towel and let the dough rise in a warm area for about 1 to 2 hours, or until it doubles in size.
Preheat your oven to 475°F (245°C).
In a skillet, heat 1 tablespoon of olive oil over medium heat. Add the shrimp and mixed seafood to the skillet, along with the minced garlic. Sauté for a few minutes until the seafood is cooked through. Remove from heat and toss with lemon juice, chopped parsley, salt, and pepper.
On a lightly floured surface, roll out the pizza dough into your desired thickness and shape. Transfer the rolled-out dough to a pizza stone or a baking sheet lined with parchment paper.
Prepare the sauce. In a small bowl, mix together crushed tomatoes, olive oil garlic, oregano, salt, and pepper. Spread the sauce evenly over the pizza dough, leaving a small border around the edges.
Spread the sauce evenly over the pizza dough, leaving a small border around the edges. Sprinkle shredded mozzarella cheese over the sauce. Distribute the cooked seafood mixture evenly on top of the cheese. Scatter sliced red onions over the seafood. Drizzle some olive oil over the pizza.
Bake for 10-12 minutes, or until the crust is golden brown and the cheese is melted and bubbly. Remove the pizza from the oven and let it cool for a few minutes. Slice the pizza into wedges and serve hot. Enjoy your delicious homemade seafood pizza!