Is it bad to lay down after eating a meal for the digestive process or your body?

Reflux Esophagitis. No, but if you are prone to reflux esophagitis commonly called heartburn, lying down after eating will make that worse. Best to stay upright for 30 minutes after eating if possible.
OK, if no reflux. Siesta, traditionally after lunch, has been advocated as healthy and digestion friendly. Unless heartburn or reflux like symptoms, probably OK.