Can I make an 88-Key Instrument using Sound Effects, or other real instruments?

Are you saying you want to sample some external sound source and play it back from a midi keyboard? Most any full sampler and many sample playback applications (romplers) will do that. You may already have one of those and not know it, but if not there are suitable applications available for free. The basic steps are pretty simple, and you can use pretty much any recording software to record the samples, but if you are planning to loop the samples, a dedicated sampler can be useful.
https://omegastudios.com/5-steps-sampling-instrument-kawai/
 

The short answer is no.
The long one is: You have to roll up your sleeves and model what the instrument in question does in a programming language or worse, synthedit / flowstone. This is not an afternoon endeavor. If you really like something your hardware instrument is doing and can replicate it in software, you may be able to drive it via midi out and record the analog sound back into a sonar audio track.
 
It's also often profitable to google the name of the unit plus the word vsti as just about everything that was ever stamped out in hardware has been copied to some degree in software somewhere.

Real easy as said, All you need is a sample player, record your samples and put them in that players library.
 
Example, I sampled my real drum kit, edited the wave files in a wave editor. And dropped those into Session drummers sample folder. Now Session drummer can play my real kit. 
We needed a hammer hitting a railroad spike for a song. did the same thing. 
Not sure how to make a sample of pitched instruments but sound effects and percussion are easy. 

Just Buy These from Waves, it's much easier.

Grand Rhapsody Piano $29.99
Electric 88 Piano$29
Pianos & Keys Currently $145. (Wait it will go down in price)
 

 

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