Some good notes on heartburn, a fiber regime, some combination of wheat dextrin, psyllium husk, inulin. All 3 are different and serve a somewhat different function.
Foods to eat, oatmeal, lentils.
Ginger tea, activated charcoal tabs.
Most all of that works very well to support gut bacteria so throwing some probiotics in as well can help. The gummy kind available in generic or Digestive Advantage work well!