Although many people claim to have seen dragons, after all, there are not enough clear photos or videos, let alone physical objects.
Therefore, the existing scientific evidence is not enough to prove that dragons exist as a creature.
However, we can say that "the dragon, as a creature, may have existed". Because although it is impossible to scientifically judge the existence of dragons, it is also impossible to scientifically judge that dragons do not exist. Because we have reasonable evidence to suspect that dragons once existed, for example, only dragons in the zodiac are not real animals, and ancient books record the living habits of dragons. There is even a view that dragons once existed all over the world, because different nationalities around the world have legends of dragons or creatures similar to dragons.
However, all the above assumptions need further scientific proof.
By the way, there is a fake documentary based on the last hypothesis mentioned above, which may give LZ some inspiration. It's called Dragon World: Fantasy Becomes Reality (see Baidu Encyclopedia for details).