Sgombro al cartoccio con padellata di piselli e asparagi- Baked mackerel with stewed peas and asparagus

This is a super easy dish, what can I do I am only now learning to cook!

-a mackerel or similar dish
-one lemon
-one small onion
-frozen pease
-asparagus chopped

1)fill the fish with lemon slices and parsley and season. Wrap it in foil and bake in the oven at 180 for 20 mins or until cooked
2)add oil in a small frying pan, add chopped onion, when soft add the asparagus then the peas, season cover with lead znd let it cook until soft.
3)serve with the fish and boiled potatoes or rigatoni pasta