Is it possible to use keyboard as output device?

example:

Midi in ---> translate midi values to key --> keyboard output to different program.

Is it possible to make tabs like in browser
That way I could put differrent options to specific page.
For example:
1st tab/page drum machine
2nd tab/page synth
3rd tab/page sampler
etc..

I can't figure out how to do that..

Please help me.