A lot of studies have concluded that there are too many variables (like age, ethnicity, culture) to actually quantify beauty and that it very well may lie in the eye of the beholder.
In my opinion, if a person is happy with their appearance, it shows and this in itself can add to someone’s beauty.
I’m probably wrong though lol
There are some near universal elements of beauty that span human cultures, like symmetry, smooth skin textures etc. larger eyes in animals. Note: I say near. There are always exceptions.
Certain physical features have been associated with reproductive fitness, proper hormonal balance, and ability to raise offspring. These features are commonly found attractive, cross-culturally. So yes, some aspects of beauty are universal. Not all, but some.