What Was Before ' the Beginning '....?

[Rahul]

‎1) what is the - source - of all these ' atoms ' , (material) from ‎which ‎‎, the first cells were assembled ??‎

Ok, well the short answer for where atoms come from is this: Immediately after the "Big Bang" there were no atoms. The elementary particles were too hot at this time to form stable atoms. After several thousand years everything cooled down enough for mainly Hydrogen and Helium to form.

I suppose you really mean is where does matter come from.

At the very beginning of the expansion of the Universe there wasn't any matter. There was only energy in the form of light (photons). Photons can spontaneously decay into particles and antiparticles and can be observed happening today in gamma rays. The matter in the universe came from this decay.

‎2) if we could move back on the ' time line ' , when was ‎the ‎beginning of this world around us ? where , the accident of ‎‎ ' cell ‎assembly ' occurred ?? and what was - before - this ‎beginning ??‎

Which are you asking? The beginning of the planet or the beginning of life?

‎3) if we could move forever in any direction , in the universe , ‎what ‎will be at the end ? is it more space ? then we still in our ‎world !!. is ‎it blocked by some material ? then what is behind …??‎
hoping to find logical answers , in order to get better ‎‎ understanding ‎to our existence..... ‎

No matter how fast or how far you traveled within the Universe you would always still be in the middle of the Universe. The origin point of the singularity where the expansion of the Universe began is about 46 billion light years away in every direction from us. No matter where we are. This is due to the fact that new time and space is continuously being created within the singularity everywhere at once.