Quantum Physics

Questions after my understanding of Quantum Physics:

If Hydrogen is the primary element in the Universe, all other elements are created only in the core of stars, in process of nuclear reactions? How do our planets have different elements with in? Is it single Big Bang or cyclic contraction and expansion of Universe is happening ? I think, the first Universe created was only with Hydrogen, it got collapsed and created other elements Big bang again, this process is keep on going on until now to create heavy elements.
If whole Universe is formed after Quantum fluctuations, what happed to those fluctuation after Big Bang? Are these Quantum fluctuation still exist, if yes what are they forming now?
What is the boundary between Quantum and Classical Mechanics?
Is it possible that, at Quantum level dual (wave and particle) behavior is normal?
How to explain Quantum transportation and entanglement ?
Are all the so called elementary particles subdivided into sub atomic particles as light as electrons/photons? Similar to materials into atoms, atoms into electrons, protons and neutrons. Nucleons into quarks and so on.
Single photon pairs generated from Spontaneous Parametric Down Conversion (SPDC) are entangled. Entangled photons behave magically, if we change property of one photon property of other entangled photon will be changed automatically irrespective of distance and position.
While Big Bang (formation of the Universe), multiple atoms are generated in a single event, are all these atoms entangled? In this case, multiple parallel universes should exist. If parallel universes exist, how far are they and what happens if they come together?
What happens, if we generate photons by Multi Photon Spontaneous Parametric Down Conversion, are they all entangled?