Initially I would like to thank all of you, for your time spending answering me!
Now lets clarify some blank spots about my initial query.
I am using a synthesizer (WSA1) as my main midi keyboard, connected to my pc, through a midi-usb adapter (doremi) and everything works fine.
Now I am using Cakewalk as DAW and I have download from spitfire Audio, the BBC Symphony Orchestra and I have learned how to set and use the instruments and record tracks.
I have create some orchestra tracks, but because after some time while recording , I don't remember every note of every instrument and because I don't read notes , I need a visual keyboard on the screen when playback... so I can add or remove or expand my musical parts.
Basically I have learned to play visually and acoustically and it is very important to me, to visual inspect what I have played initially.
I hope I made clear my blank spots of initial query