Quarks and leptons all have 1/2 unit of quantum spin and are called fermions. All quarks, electrons, neutrinos, muons and tauons are fermions. There is a second family of particles called the bosons which include photons, W+, W-, Z0 and gluons. These are the force-carrying particles that cause the electromagnetic, weak and strong forces. They have 1 unit of spin. Some physicists believe that the gravitational force is carried by 'graviton' particles which have 2 units of spin. There may also exist Higgs bosons which carry 0 units of spin.
You must understand that quantum mechanical 'spin' is not to be thought of as being equivalent to the spinning of a top or a planet. Heisenberg's correspondence principle states that to find the classical analog of any quantum property, you increase the corresponding quantum number to very large values. This works for energy, but for quantum spin, you may not vary this quantum number beyond the range from 0 - 2. As you see, there is a deep connection between quantum spin, and how the particle functions in the above list. 1/2 unit spin fermions are the basis for the structure in the physical world; the various bosons act upon the fermions to confer mass ( Higgs mechanism), cause gravity ( graviton exchange) or the other forces.
We don't know where spin comes from. This is like asking why is there gravity in the universe. It just is, and is another one of those imponderable features to our world that philosophers get to worry about.