a big subject, I'm afraid.

technics format is a proprietry format for all the dedicated features on the keyboard. it is not universal because no one else uses technics features.

to play on the pc, you need a universal format.

you could transform your creation into a midi file and save it. this is a universal format, but uses no easy play features or technics voices. so some editing is needed for a decent result.
this will then play in media player with whatever gm sounds your pc soundcard has. this will generally not sound as good as the original.
you could use media player to trigger the KN gm sounds down the midi lead if you wanted.

the easier option is to record the audio on the pc. this maintains most of the sound quality (or all with good equipment). but the wave file will be very large, suitable only for saving on cd. there are many free programs to convert the audio to mp3 format. this uses less space on the computer but cannot be played back in most cd players. and still won't fit on a floppy.