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I've been playing piano/keyboards for 35 years. I definitely don't play at a "professional" level, but I gig locally, and can play pretty well by ear, and in an ensemble. I'm not an amazing player, but I have enough experience to know something about what you're talking about.

What you're asking about is impossible. Not just difficult. You might be able to learn something about moving your fingers independently with rhythm on a computer keyboard. But at about the time you get to one week of experience, you'll probably be doing at least as much harm as good in terms of learning to play piano music on a computer keyboard. It is too different.

Partial list of problems:

  Size of keys
  Position of keys
  Number of keys
  Travel distance of keys
  Velocity sensitivity of keys
  Sufficiently low latency of audio output (can be solved with pro audio hardware)
  

To give one quick example of a deal-breaker, on a piano, you can comfortably, and in a neutral hand position, put your thumb and four fingers on 5 consecutive white keys. The layout of a computer keyboard doesn't allow for this at all.