This page covers steam irons.
Steam irons are quite often seen at Restart parties. They can be challenging to open, and as with any appliance which mixes water and electricity the fault can often be due to a failure, ultimately, to keep them sufficiently apart.
Usually there will be one or two easily accessible screws at the back of the handle but these may only release that part of the handle. Another screw or screws near the front may be hidden for example under the steam button, but even after removing these the handle cover can be tricky to remove. Often there will be a series of clips down the sides, but this may not be all. In the iron illustrated there was another clip to be released on the top just forward of the cable which required the whole of the top cover to be pushed forward.
With the top cover off it should be possible to find the screws which release the whole of the plastic top, in order to access the thermostat etc. and (if not already accessible) to replace the mains lead.
On reassembly, ensure that any tubes associated with the water reservoir and steam delivery are properly connected.