First make sure it is really hot by sprinkling some small amount of water on the block- If it sizzles-your gauges are not lying.

Next, are the fan/fans running? That will be either the radiator temp sensor, low coolant,bad fan or bad fan wiring. First- direct wire the fans to the battery. If their good, connect the wires at the sensor together (you may have to turn on the ig). If they don't run the fan, see if the hot lead to the rad sensor really is hot. See if the ground wire from the fans is good. Follow back any faults to the main fuse block and beyond.

Next would be the thermostat. Is the place top hose is connected to. Put thermostat in some hot water and watch it open. Next in the freezer and watch it close.

Check your oil for water/coolant in quantities undesirable. If there is water in there, you have some bigger problems.

Last- though maybe should be first- is there a cat spread eagle cross your radiator - or a piece of plastic sack or something. Are the AC fins clean can you take a garden hose a spray water thru thu whole mess, what about the inside of the radiator" ? Any pensoil white scum or growth?

That will give you some direction. Hope it's one of the cheap problems