So, this may come as a surprise to many of you, but race, just like gender, is a social construct.
There is no underlying biological differences between races, the differences we see on the outside are nothing more than skin deep (pun intended).
The idea of a white race was not even a concept until colonial times when there was a need to justify slavery and maintain control of wealth and property.
Over time, the definition of who qualified as white changed. In times past the following groups fought socially and through the courts to be considered white: Italians, Irish, Greeks, and Poles.
Clearly this is not to say that our social construction of race is not important or that does not have a profound impact on the individual and society. But I think it is important to know the context of the origin and function of the concept of whiteness.
If you are interested in furthering your education around race, there are a couple of good books to take a look at:
So You Want to Talk About Race by Ijeoa Oluo (a Nigerian-American woman)
White Fragility by Robin Diangelo (a White woman)
A Race is a Good Thing to Have by Janet E. Helms (a Black woman)
How to be an Antiracist by Ibram X. Kendi (a Black man)