I don't know what you mean by indigestion but based on what specific symptoms people actually have when they complain of "indigestion", drinking water won't help. In fact, drinking water is not a solution to any GI problem, really.

No, eating better food can and try taking a pepcid before a meal like that it will help. In the long run, if you are getting heartburn you might want to eat slower, yes, more water and better food.

If this is a chronic problem then please get definitive treatment for the problem. Do not ignore it please.

Yes, by DILUTING "spicy food irritants" and increasing the "pH" of the stomach, it MAY reduce sx. But, you may also have GERD, GASTRITIS, or ULCER dz -- which may all need lifestyle changes and/or medication to reduce GASTRIC ACID (and antibiotics if you have ULCER disease associated with H. Pylori infection).