That's a lot of orange peel. You'd have to wet sand first and then polish it again. Because of the curve it's in, you'd probably need a rotary or forced rotation polisher to remove the sanding scratches, a DA would stall like crazy there.
Since it's a small area, it might be cheap and easier for you to pay a pro to handle it. Also because it's near edges and wet sanding that could be dangerous and if you sand through the clear, then you'll have to get it painted again.
I hope that paint job was cheap because the painter sure didn't even try to make it look like the rest of the car, that's way too much orange peel.