To dissect a fish, one needs a chopping board, sharp knife or scalpel, tweezers, and scissors. The process involves examining the fish's external structure, making an incision from anus to neck to expose the internal organs, and then locating and examining the heart, liver, stomach, intestines, eggs, and bladder. Dissecting the eye carefully to find the lens and examining the mouth and gills are also part of the process. Dissecting fish provides children a hands-on way to learn anatomy and biological structures.