Isn't it true not even one skeleton of a something morphing into another something has never been found?
Most fossils just lay there, yes. However, many fossils are intermediate in form between those found earlier and later. The fossil record outlines a branching tree of life much like those derived from studying the morphology of currently extant life and (more recently) molecular biology.
Darwin, faced with a much, much less complete fossil record in 1859 than we have now, was reduced to predicting that a lot of intermediates must have existed and would turn up when more of the world was investigated. Many scoffed, but he was right. Virtually all of the previous examples are post-Darwin. If he wasn't right, he was the luckiest charlatan in history. How did he do that?