Yes. Coelenterates are the same as Cnidaria.
Coelenterates are, in fact, an olde Phyla. I believe that they are known as Cnidarian. I wish you the best of luck in researching their different body types. Firstmate...
They usually live on salty and fresh water.
The term 'phylum coelenterata' means hydras; polyps; jellyfishes; sea anemones; corals
Your life.