where is cylinder# 3 on my Kia Rondo Ex 6 cylinders?I have a cylinder3 miss fire on 2007 Kia Rondo

I received a code say that it was a cylinder 3 miss fire. I changed the spark plugs and still doing it. Do I need to change the injector or the ignition coil?
Kia Rondo Ex (6 cylinders)

Asked by for the 2007 Kia Rondo
Middle cylinder on firewall side of engine. Starting at serpentine belt side on engine Firewall 1 3 5
Radiator side 2 4 6.