The Marvel Cinematic Universe has introduced countless heroes with varying levels of popularity. But the one thing almost all have in common is that their origins were explored deeply. In the case of Iron Man, the story of a genius engineer forced to survive after being kidnapped by terrorists was almost exactly like the origin of the comic book. Captain America was another example of a perfect retelling of the character's origin on the big screen. But for every identical retelling, others diverge heavily from what the comics offered.
Source：https://www.cbr.com/spider-man-mcu-origin-unfaithful-source-material/
