The best fantasy worldbuilding always starts with really asinine questions. Not even basic stuff like “how do they get their food?”. I’m talking much more trivial: stuff like “are their swear words more likely to be obscene, scatological or blasphemous?“ or “what kind of hats do they wear?” - that’s your gold mine, especially once you add “and why?”.
In my campaign it’s rude to refer to reptilian races as lizards unless there actually lizardfolk mostly because calling dragonborn and kobalds lizard would essentially be like saying all reptiles look the same