I had an egd and was diagnosed with "diaphragmatic hernia". what is that and what can i expect moving forward?

Depends: What your doctor may have meant was you have a hiatal hernia. This may or may not be symptomatic by contributing to symptoms of relux, heartburn, and pain. If so it can usualy be treated medically. Medical treatment failing surgery is always an option. Surgery can be done laparoscopically and recovery is short term.

Paraesophageal herni: It is unlikely you had a diaphragmatic hernia. Rather you had a paraesophageal or sliding hernia. This means a portion of the stomach either came alongside the esophagus(food tube) or the area where the esophagus connects to the stomach is above the diaphragm. The normal hole through which the stomach/esophagus pass is too big ;may need repair.Diaphragmatic hernia-congenital/traumatic prob.

Hiatal hernia: This is a hiatal hernia, and they are usually nothing to worry about unless they are large. These large hernias are referred to as paraesophageal hernias, and may need surgical repair. Small hernias can enlarge with time, but it takes years or decades to do so. Ask your GI doc or primary care for more info. Hope this helps!