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For me it seems nearly impossible that two different branches of evolution came up to same organ or feature.
Is there any proof or refutation that every organ or feature was inherited from common ancestor?
Is there any mechanism of adopting organs or features from different branches?
Example of organs and features:
This question seems relative a bit: What is the evidence that plants and animals had a common ancestor?
It seems that some features/organs could appear during evolution independently for different branches of evolution.
https://www.scienceworld.ca/stories/evolution-flight/
Flight appears to have evolved separately four times in history: in insects, bats, birds and pterosaurs. These four groups of flying animals didn’t evolve from a single, flying ancestor. Instead, they all evolved the ability to fly from separate ancestors that couldn’t fly. This makes flight a case of convergent evolution.
For chordates and, more specifically, vertebrates, most organs do share a common ancestry. Some organs with different functions share the same origin too. For example: cephalochordates have a iodine mucus-producing gland called endostyle, which roots back to the first protochordates. Its function is to capture microorganism and detritus. In vertebrates the endostyle became the thyroid gland, which obviously has a different function but still secretes iodine.
However, if we take a look at Metazoa in general (=basically all animals grouped into one taxon) some organs definitely have different origins because of convergent evolution. For example, vertebrates and cephalopods both share camera-type eye and a similar central nervous system but those features evolved separately. Same thing applies for arthropod hearts and cardiovascular system compared to vertebrates’ one. Both have a closed circulatory system but that’s a certain case of convergent adaptation, since deuterostomes’ and protostomes’ last common ancestor was an acoelomate and didn’t even have a cardiovascular system in the first place.
"For me it seems nearly impossible that two different branches of evolution came up to same organ or feature."
Depending on what level of organization you are talking about ("feature" is rather imprecise), the answer differs somewhat, but in general it is quite possible and instances are known, as laid out a bit in other answers.
If you are talking about an "organ", depending on what you mean, the panda's thumb might be an example, or eyes.
What's instructive about the example of e.g. cephalopod vs. vertebrate vs. insect eyes is that while they are quite different structures, they are all actually quite similar at the molecular level, for example using homologous opsin proteins, chemical processes, and in fact arising from the same ancestral tissue lineage. The case is instructive in that the evolution was parallel, arising from a shared set of input components among all lineages, rather than convergent, arising in a totally de novo fashion (though in general people seem to prefer "convergence" as the more general term). This kind of parallel evolution is much more frequent than completely independent convergent evolution.
More generally, convergent evolution occurs more frequently between closely related lineages than between distantly related lineages, arguing that the shared evolutionary context makes it more likely that the same adaptations can occur. Similarly, such convergence tends to reuse the same molecular components rather than to derive similar components independently.
It is true as a general rule, with exceptions.
The catch-all terms in your list belies the differences that exist. There are radically different kinds of eyes. For example, your eye, insect eyes, octopus eyes, and lobster eyes are all wildly different. The same is true with lungs (invertebrate lungs vs vertebrate lungs). This is also true with hearts, limbs, ears, mouthparts, and taste/smell organs
For the eye, specifically, it would not be surprising if we were unsure whether it can be evolutionized to a single initial version of a primitive eye. The issue is that if you go far back enough we just aren't sure due to lack of fossil evidence. The simpler things are, the less variation there can be and the more likely two independent things will end up the same. If there were a common origin for all eyes, it would likely be a light sensitive organelle on the microorganism level and you can see why fossil evidence for such a thing is tricky to discern even if found it.
Even going as far back as the mysterious Pre-Cambrian may be insufficient. Jellyfish, molluscs, and worms (our ancestors) already existed, and likely arthropods (marks that look like leg tracks have been found), all of which are known to be capable of light sensitivity...in modern times at least.
But let's not forget plants can detect light too and they go back even farther so that could be your evidence for convergent evolution of eyes...but again, it's also not a sure thing unless you can find and compare genetic evidence for light sensitivity between living plants and animals).
But eyes are a difficult and unnecessary example if you just want completely independent convergent evolution examples. Legs are dead easy. Arthropods and "fish" diverged before the "fish" even had fins (from which limbs would evolve for all tetrapods), and arthropods already had legs.
Another easy one is wings between insects, bats, pterosaurs, and birds. Less "optional" structures such as internal organs (and especially body symmetry) tend to go back really far and make things difficult.
