Rinse fish fillets under cold water; pat dry. In shallow dish, beat eggs. In another dish shallow dish combine potato flakes, Parmesan cheese, and oregano flakes. Dip fish fillets in egg, coat fish with potato flake mixture. In a large skillet heat oil over medium for 1 to 2 minutes. Fry fish in skillet until crust is golden brown and fish flakes easily with a fork, about 3 to 5 minutes on each side. Season to taste.