It is a soft synth, a sample playback synth. It comes loaded with Programs (patches in synth speak).
You insert it into a DAW - or standalone. Read the manual for your DAW if the former.
You choose a program - a sound. Read the manual. Play a sound for an external midi keyboard. Read that manual and set it up. Record the sound and proceed with your song construction.
It may seem like a lot of reading, but it does take time.
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https://soundcloud.com/a-pleasure-dome
http://www.bnoir-film.com/ there came forth little children out of the city, and mocked him, and said unto him, Go up, thou bald head; go up, thou bald head.
24 And he turned back, and looked on them, and cursed them in the name of the Lord. And there came forth two she bears out of the wood, and tare forty and two children of them.