To find the correct answer, we have to look at the words used rather than just the numbers. The trick is understanding that the actions described are a sequence of events happening to the same  eggs, not different groups of eggs.
1. The Starting Point

You begin with a total of 6/6 eggs. This is your initial inventory.
2. The Actions Taken

The riddle mentions three specific actions:

Breaking the eggs: You cannot fry or eat an  egg without breaking it first. So, you take 2/6 eggs and break them.
Frying the eggs: Now, you take those same 2/6 eggs that you just cracked open and put them in the pan to cook.
Eating the eggs: Finally, you eat those same 2/6 eggs that you just fried.

3. The Sequence