IF Darwin could have seen the complexity of the single cell, Darwin would have given up on his theory of the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life...
Francis Crick, co-discover of DNA said that there was no way it just happened by chance. A complex code that was used to create every living thing.
Of course he couldn’t attribute it to God, so he figures aliens sent the DNA code out into space to populate other planets. Pansperma he called it IIRC.
Although that just shifts the evolution off to another planet.
Even some evolutionists admit that gradual evolution isn’t shown in the fossil record. (Darwin thought that the study of fossils, becoming more important at his time, would find
more discoveries showing gradualism.) Now they theorize “punctuated equilibrium” where things are gradual until one healthy mutant happens along that creates a whole new thing. The “hopeful monster” they call it.