Hello and welcome. The issue seems to be excessive gas accumulation causing abdominal bloating, possibly even tenderness and thus a drop in appetite. But I would also advise an upper abdominal endoscopy just as a diagnostic test to help rule out any abnormalities with the upper GIT. Once this is done and an upper GI endoscopy is ruled out, then we can purely suspect the gas accumulation to be the cause for your symptoms. Eat a high fibre diet, drink plenty of fluids, avoid spicy food, avoid smoking, avoid alcohol, avoid fatry/fried/oily food, and go about mild exercises to promote quick digestion and prevent stagnation of food. Best wishes.