Peace Be Upon You.
So let's suppose that what Darwin said was right, Humanity has evolved from Apes
I congratulate you on your enquiry and willingness to learn.
Perhaps the place to start is to understand what the theory of evolution actually shows.
The earth is some 4.5 bn years old, and formed at the same time our solar system was forming, so the sun and other planets are roughly of the same age.
According to fossil and geological evidence, life arose on earth more than 3.5 bn years ago.
The study of abiogenesis looks for how the first self-replicating cell came into existence. At present we have no clear description of this transition from chemistry to biochemistry, but the study is ongoing and there has been steady progress.
Evolution starts once that cell is in existence. It occurs because although the product of replication may be biochemically identical to the original, there will be times when it is not. The variation in the newer cell may be beneficial, or neutral, or detrimental. In the first two cases, the newer cell will be able, or more able, to survive and to self-replicate in turn, and its new cells will carry the variation. If the variation is detrimental then the newer cell will be less likely to thrive. As the cell becomes more complex, the ways in which variations may occur increase in number.
The outline for human evolution looks like this ─
Human evolution goes from the most basic form of life (protobionts, presently undefined)
to the single cell (Prokaryota) 3.5 billion years ago (bya)
to nucleated multicelled (Eukaryota) [though some say Eukaryota came before or simultaneous with Prokaryota] 1.7 bya (and around this time the first living things having two sexes appear)
to bilateral symmetry (Bilateria) ›555 million years ago (mya) (that is, the left side is the mirror image of the right side)
to a stomach with two openings [mouth and anus] (Deuterostomia) ›555 mya
to a notochord [‘spinal chord’] (Chordata) ›555 mya
to a backbone (Vertebrata) ›525 mya
to a movable lower jaw (Gnathostomata) ›385 mya
to four legs (Tetrapoda) ›385 mya
to eggs with water retention suitable for dry land (Amniota) ›340 mya
to eye sockets each with a single opening into the skull (Synapsida) ›324 mya
to mammal-like reptiles (Therapsida) ~274 mya
to ‘dog teeth’ (Cynodontia) ~260 mya
to milk glands (Mammalia) ~200 mya
to vivipars (giving birth to live young) and monotremes (egg-laying mammals) (Theriiformes) ›160 mya
to modern vivipars (Holotheria)
to proto-placental mammals and marsupials (Theria)
to placentals and certain extinct non-marsupials (Eutheria) ›160 mya
to placentals (Placentalia) ~110 mya
to all mammals except the Xenarthra [sloth, armadillo, anteater] (Epitheria) ~100 mya
to bats, primates, treeshrews (Archonta) ~100 mya
to tarsiers, monkeys, apes (Haplorrhini) ~63 mya
to New and Old World monkeys and apes (Simiiformes) ~40 mya
to Old World monkeys and gibbons (Catarrhini) ~35 mya
to apes [great apes and gibbons] (Hominoidea) ~29 mya
to hominids / great apes [orangutans, gorillas, chimps, Homo] (Hominidae) ~25 mya
to hominins [gorillas, chimps, Homo, H. floresiensis, then or else later H. Denisova] (Homininae) ~4.5 mya
to Homo [H. sapiens, H. Neanderthalis (Homo) ~2.4 mya
to Homo sapiens [Homo sapiens Idaltu, Homo sapiens sapiens] (Homo sapiens) 250 kya
to Homo sapiens sapiens ─ that's to say, us.
(If you have any trouble with the vocabulary, just google the word.)
Does Darwin's theory only apply on Human beings and Apes?
No, as you can see it applies to ALL living things on earth, including huge numbers of kinds that have lived in the past but are now extinct, so that we know of them only from the fossil record.
May I ask what is the origins of Apes? or Maybe even the origins of origins of Apes.. May I ask the main origin of all biological creatures on Earth?
See above. As to where we're up to with abiogenesis, you might like to read this
>link< and that will give you a basis if you want to go into more detail.
If Darwin's theory is correct then it should lead us to 1 single living organism and from this organism every other creature was developed and originated throughout thousands or even millions of years
Yes, indeed billions of years.
but then we say.. what was the origin of this single creature or this single organism?
See the link above. Abiogenesis is a work in progress ─ we know THAT life arose on earth all that time ago, but we're still working on the HOW.
Good hunting as you explore these scientific questions!