Wow, this is a whole field of it’s own.
Assume we’re talking fins and gills type of fish and leaving aside shellfish and other marine life, fish usually comes in one of these forms:
Whole. With skin on, usually cleaned. Usually baked. Small fish may be battered and fried. The inside of the fish can be stuffed, the outside can be covered with a sauce. For small fish like brook trout, stuff the insides with savory and/or spicy herbs, wrap the fish with bacon slices, bake until bacon is done.
Steaks. Cuts across the body of a firm fish. The skin may or may not be left on. The spine and ribs may or may not be removed. This would be a section of a whole fish for something like salmon, or a section of a half loin for a large tuna or swordfish. Bake,broil, or steam. The cuts may be too thick to pan fry properly if the fish is not very firm like tuna.
Loins, filets, sides, other names. Half of a fish split along the spine. Almost always spine and ribs are removed. Sometimes with skin, sometimes without. Bake, broil, pan fry, or deep fry. When baking, the fish may be stuffed, which is a layer of stuffing on top of the filet, between two filets, or the filet may be rolled up with a layer of stuffing. The stuffing is usally breadcrumb, herbs, butter, and may contain other meats or shell fish like shrimp or scallops. For broiling, anything on top of the fish may burn, so just smear some butter or oil over the fish, with minimal seasonings. Pan fry in hot oil, breaded, lightly floured, or plain. Fry the top first, then finish on the bottom or skin side. To deep fry, cut into serving size pieces, batter or dry bread and fry in hot oil.
I’m not a fan of marinades on fish, it’s easy to kill the flavor, but citrus marinades are popular.
People will groan, but you can make excellent fish in a microwave. Use firm white fish like cod, cut into small thin pieces and arrange in a layer on a heavy plate. Throw on some parmesan or mozzeralla cheese if you like, top with bread crumbs, herbs, and some butter. Microwave uncovered for 5-7 minutes. The fish will be tender and delicious. This is good for scraps left over from trimming fish.
Most fish will benefit from salt and butter. I like to use dill with seafood. I’ll follow up later on with some specific recipes.