IF the refineries are protected target the factories making military equipment (bombs, drones, shells…). Target the airplanes and launch systems for those. There are a lot of targets, refineries are good if the people can put enough pressure on the government to stop the war, but otherwise the military gets priority for what fuel there is.

I don’t recommend oil wells just because you have to get so many before it makes a dent. Also they are likely to be easy to repair even if you do get one (depends on how it is hit). There is other oil infrastructure that is worth hitting.