Do platyhelminthes have an entoderm

Yes. platyhelminthes have an endoderm

Explanation:

Platyhelminthes are mostly worm like creatures that are dorsoventrally flattened,bilaterally symmetrical, body having 3 layers of tissues with organs and organelles and body contains no internal cavity i.e acoelomates. The three layers of tissues include ectoderm, mesoderm and endoderm.

the abdomen (less formally called the belly, stomach, tummy or midriff) constitutes the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. the region occupied by the abdomen is termed the abdominal cavity. the stomach secretes acid and enzymes that digest food. ridges of muscle tissue called rugae line the stomach. the stomach muscles contract periodically, churning food to enhance digestion. the pyloric sphincter is a muscular valve that opens to allow food to pass from the stomach to the small intestine.