I cool my house at the Jersey shore with a 1-ton unit I installed - nice and quiet and does a great job in this 94 degree weather with swampy humidity outdoors.
The outdoor unit sits on a slab or can be suspended from the eaves with rod. The indoor unit is fastened to the wall or ceiling. The two are connected by one small copper tube and one larger copper tube usually using flare fittings. A passage will have to be cut in the wall to pass the tubing, wiring and condensate drain line.
The major skill is in cutting, deburring and carefully flaring the ends of the tubes, after having slid the flare nuts on the tubes so they can be properly tightened on the flare fittings on the units. The refrigerant skill is to evacuate the tubes of all air and then charge them from the unit with refrigerant. The electrical skill is to attach the proper size 220 volt electrical wires. This is shown on the wiring diagrams that come with the unit.
It is a good idea to have taken a hands-on installation skills course in air conditioning first.