As a parent, do you force your kids to eat all of their food?

For me No. Only two rules.

-Eat a teaspoon full of everything so you know what you are rejecting
-If you come back saying you are hungry before next mealtime, you get what you rejected before, heated up if appropriate,

Informally, adults can tell when they really don't like it, and adjust future menus accordingly. But children won't starve if there is food, any food, available. (Weird medical conditions excepted).