No you do not feed the oatmeal to the fish. If you have a microworm culture, the oatmeal should be on the bottom of the culture container and you wait until the worms are crawling up the side of the container. Then you wipe some of the worms off the side with your finger, and wiggle your finger in the water with the fry.
Microworms are not as nutritious as newly hatched brineshrimp but they have some benefit when used as part of a varied diet.