Is this difficult to install?

They are fairly easy to install. They come with directions that average homeowners can follow for changing out the old receptacle to installation of the new receptacle.

It's not difficult for me, but I have no way of knowing your skill level. Electric ranges do not come with a cord/plug, they are purchased separately. The 50 amp range receptacle you selected is for 3-wire range circuits installed prior to 1996 and should be installed in a 4" square box recessed in the wall. The circuit should have two hot conductors, probably black and red, and one neutral conductor which probably is white or bare if SEU cable was used. There are markings on the back of the receptacle to indicate where the wires go. If the circuit has been installed since 1996 you need a 4-wire range receptacle. Purchase a cord/plug to match the appropriate receptacle.