As a marine biologist with a focus on echinoderms, which includes starfish, I can provide an informed answer to your question.

Starfish, also known as sea stars, are not capable of swimming in the traditional sense like fish. They do not have fins or any specialized swimming structures. Instead, they move by using their tube feet, which are small, muscular, and water-filled appendages that extend from their underside. The movement is a combination of hydraulic action and muscle contractions. By extending and contracting their tube feet, starfish can crawl along the ocean floor, but they are not swimmers.

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Starfish are not actually fish; they're marine animals from taxonomic family Echinodermata. Three distinct types of starfish or sea stars exist, but thousands of species exist within those types. Starfish don't swim, but they do manage to move along the sea floor or on reefs by an unusual process of locomotion.read more >>