I love to eat shellfish, its one of my fav kinds of food
It is good. Shellfish is a culinary and fisheries term for exoskeleton-bearing aquatic invertebrates
Yes my favorite is shrimp
I have herd  some kinds are found in freshwater.
Lobster is delish as well!
They are! a few species of land crabs are eaten, for example "Cardisoma guanhumi"
I have never heard of that are they good?
They are and shellfish are not a kind of fish
How are they served or cooked?
shellfish are low on the food chain and eat a diet composed primarily of phytoplankton and zooplankton. Many varieties of shellfish, and crustaceans in particular, are actually closely related to insects and arachnids; crustaceans make up one of the main subphyla of the phylum Arthropoda. Molluscs include cephalopods (squids, octopuses, cuttlefish) and bivalves (clams, oysters), as well as gastropods (aquatic species such as whelks and winkles; land species such as snails and slugs).
Molluscs used as a food source by humans include
Shellfish
Shellfish is a colloquial and fisheries term for exoskeleton-bearing aquatic invertebrates used as food, including various species of molluscs, crustaceans, and echinoderms. Although most kinds of shellfish are harvested from saltwater environments, some are found in freshwater. In addition, a few species of land crabs are eaten, for example "Cardisoma guanhumi" in the Caribbean. Shellfish are among the most common food allergens.
Despite the name, "shellfish" are not actually fish, but are simply water-dwelling animals. Most