why do cells duplicate? NOT HOW and can't we create a duplicating cell from raw elements?

You and everyone else.

Short answer: because genes want to reproduce copies of  themselves.

Longer answer: read Dawkin's "The Selfish Gene".

As far as making one, we're getting there. There's a whole field devoted to it: synthetic biology.

everything is the result of a long string of chemical reactions, it's not untill you get conciousness that life forms actually "decide" to reproduce.

The best answer that Science can give you at this point should be as obvious as it is un-satisfying.

It's because things that duplicate themselves are a lot easier to find on this Earth than things that do not duplicate themselves.

The problem is that science only answers what, where, and how.  Why has no empirical meaning, and isn't based on objective observation, so it is outside of the scope of science.

The closest that you can get to "why" is that the non-dividing primordial cells didn't divide, and therefore didn't establish any lineage.  If none of the first cells replicated, then we wouldn't be here now to ask why.

Theoretically, we should be able to create a cell de novo from elements.  The problem is that it would take far too long.  We'd need a test tube the size of the combined oceans of earth, under very specific conditions, running for about a billion years to generate the simplest proto-life.  We know what a cell is made of, and largely how it works, we just don't have the technology to put it together yet - once we've advanced in that area, then maybe we can shave some time off of the billion years necessary.