Dismissing ethics seems unfair. How do you propose we approach the question of what we aught to do, or even decide how we go about deciding what we aught to do

Dismissing ethics seems unfair. How do you propose we approach the question of what we aught to do, or even decide how we go about deciding what we aught to do, if we don't approach it through philosophy? There are many contexts this appears in: medicine, war, politics, economics, day-to-day trivialities, etc.