I am making strawberry shortcakes for Easter dessert Recipe calls for oatmeal and I only have the quick cooking can I use that ?

I think for baking, the difference would be more textural than flavor - with old fashioned rolled, it might have a slightly more 'oat-y' texture; and since quick cooking is already partially broken down, it would be a bit smoother texture.

I'm guessing you are adding the oatmeal to the biscuit dough. I think it should be okay, as long as the oats are the old-fashioned, rolled kind and not the steel-cut kind.