Preheat the oven to 400°F (200°C).
Rinse the fish fillets under cold water and pat dry.
Place the fillets on a baking sheet lined with parchment paper.
Drizzle olive oil over the fish and season with salt and pepper.
Arrange mixed vegetables around the fish on the baking sheet.
Squeeze half a lemon over the fish and vegetables.
Place lemon slices on top of the fillets.
Bake in the preheated oven for 15 minutes until the fish flakes easily.
Garnish with fresh herbs before serving.