This article from Sapiens (“Is romantic kissing a human universal?) explains that kissing (romantic kisssing rather than the kind of kiss a parent gives a child) is surprisingly uncommon around the world. You’d never know it if you went by most movies (see, for example, “Most iconic movie kisses of all time” from InStyle, or tons of YouTube movie clip collections titled “Best movie kisses of all time”).
Iconic movie kiss #6: from “The Lady and the Tramp” (Japanese title: 「わんわん物語」
A few excerpts from the Sapiens article:
“In Melanesia, the Trobriand Islanders regarded kissing as ‘a rather silly and insipid form of amusement’
“even chimpanzees and bonbobos kiss”
“In fact … less than half of the (168) cultures we sampled engage in the romantic kiss.”
“Societies with distinct social classes are usually kissers; societies with fewer or no social classes, like hunter-gatherer communities, are usually not.”
And there are two theories about how romantic kissing originated. Try skimming the the article to find them.