Webster [1] traces the source of the word “character” to theater where it was used as an emblem of the reputation of someone or a group of people, similar to how you would recognize the brand name engraved into a thing. The interpretation that character is a result of “engraving” through repeated behavior (at the individual level) is fascinating, but doesn’t seems as supported from original usage for centuries.
[1] https://www.merriam-webster.com/words-at-play/word-history-o...).