Install ceiling light with wireless switch
The way house wiring is done in practice one cannot simply wrap an insulation piercing tap around a wire and get power. This is done all the time in cars, but not in houses. If a wire in the attic happened to be passing over the center of a room where you wanted a ceiling fixture, code and practice do not allow a simple tap.

Nevertheless, it is easy to get power to a ceiling fixture by cutting a wire and making proper connections. To tap into a circuit this way one usually is required to make two cuts and add some cable in between in order to get enough slack to make all the proper connections.

Hard wired wall switches are still the standard for controlling ceiling fixtures, but no doubt remote switching is possible. Check the electrical inspection where you are to see if what you are contemplating is allowed by the local code.

EDIT

If there is a switched receptacle in the room, then the standard thing to do would be to add a cable from the switched receptacle to a new ceiling box. The cable can always go from the switched receptacle or may from the switch box IF there is a neutral there.

Sometimes the switched receptacle is one of a duplex receptacle and the other receptacle is always powered. If so, then both receptacles can be made always powered. You might not need a switched receptacle, if there is an overhead light which is switched